• Title/Summary/Keyword: Digital IF

Search Result 2,221, Processing Time 0.026 seconds

New Electrode Shape for High Xe-content Gas in AC PDP

  • Park, Cha-Soo;Choi, Joon-Young;Kim, Goon-Ho;Kim, Joong-Kyun;Kim, Dong-Hyun;Lee, Ho-Jun;Park, Chung-Hoo
    • Journal of Information Display
    • /
    • v.4 no.4
    • /
    • pp.13-18
    • /
    • 2003
  • One of the most important issues in AC PDP is the improvement of luminous efficiency. One possible method for achieving this aim is by increasing Xe partial pressure in discharge gas mixture. The increase of Xe ratio, however, causes the driving voltage to rise, even if brightness is increased. In this study, a new electrode shape is proposed. A test panel fabricated by using a new electrode shows that efficacy has improved by 25 % and sustain voltage has decreased by 20 % compared with the conventional structure.

A Study on Church of the stage LED lighting system equipment cases (무대영상용 LED 조명 시스템 설비의 활용 가능성에 관한 연구 - 교회의 시공사례를 중심으로)

  • Lee, Jang-Weon
    • Journal of The Korean Digital Architecture Interior Association
    • /
    • v.11 no.3
    • /
    • pp.61-67
    • /
    • 2011
  • This study examined the P Church in the Large chapel and S Church in the midium chapel were Analyzed to the installed stage broadcast lighting system. As a result of the installation of lighting equipment of LED class in P Church in the Large chapel, it provided clearer image and did not have shadow. While tungsten halogen illumination was very hot and heated to be preaching, LED was not heated so the pastor was very comfortable for preaching. S Church in the Midium chapel due to low ceiling height using LED lighting musical, theater and possibly were directed. If a similar structure of Dae-Hak Street theater to replace the existing fixtures by LED lighting, rendering effective and energy saving effect is thought to have much effect.

Polar Transmitter with Differential DSM Phase and Digital PWM Envelope

  • Zhou, Bo;Liu, Shuli
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.14 no.3
    • /
    • pp.313-321
    • /
    • 2014
  • A low-power low-cost polar transmitter for EDGE is designed in $0.18{\mu}m$ CMOS. A differential delta-sigma modulator (DSM) tunes a three-terminal voltage-controlled oscillator (VCO) to perform RF phase modulation, where the VCO tuning curve is digitally pre-compensated for high linearity and the carrier frequency is calibrated by a dual-mode low-power frequency-locked loop (FLL). A digital intermediate-frequency (IF) pulse-width5 modulator (PWM) drives a complementary power-switch followed by an LC filter to achieve envelope modulation with high efficiency. The proposed transmitter with 9mW power dissipation relaxes the time alignment between the phase and envelope modulations, and achieves an error vector magnitude (EVM) of 4% and phase noise of -123dBc/Hz at 400kHz offset frequency.

Ordinary B-tree vs NTFS B-tree: A Digital Forensics Perspectives

  • Cho, Gyu-Sang
    • Journal of the Korea Society of Computer and Information
    • /
    • v.22 no.8
    • /
    • pp.73-83
    • /
    • 2017
  • In this paper, we discuss the differences between an ordinary B-tree and B-tree implemented by NTFS. There are lots of distinctions between the two B-tree, if not understand the distinctions fully, it is difficult to utilize and analyze artifacts of NTFS. Not much, actually, is known about the implementation of NTFS, especially B-tree index for directory management. Several items of B-tree features are performed that includes a node size, minimum number of children, root node without children, type of key, key sorting, type of pointer to child node, expansion and reduction of node, return of node. Furthermore, it is emphasized the fact that NTFS use B-tree structure not B+structure clearly.

Constraint Condition of the Loop Filter for the Convergence of Random Jitter Accumulation in Digital Repeater Chain (디지털 중계단에서 랜덤 지터 누적의 수렴을 위한 루우프 여파기의 제한조건)

  • 유흥균;안수길
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.24 no.4
    • /
    • pp.548-552
    • /
    • 1987
  • The constraint condition of the loop filter is persented for the convergence of the random jitter accumulation fo the 2-nd order PLL (phase-locked loop) circuit used in digital regenerative repeater. This condition is confirmed under the assumption that the number of repeater chain is 5, bandwidth is 100. 0KHz, the power spectral density of white Gaussian noise is 1.0x10**-6 [W/Hz]. Also, it is shown that if the condition is satisfied, the accumulated random jitter and the alignment jitter will have the saturation characteristics.

  • PDF

Design of Digital Controllers with Self-Validating Intelligent Sensors (Self-Validating 지능형 센서를 사용한 디지털 제어기의 설계)

  • 나승유;배희종
    • Proceedings of the IEEK Conference
    • /
    • 2000.06e
    • /
    • pp.51-54
    • /
    • 2000
  • We are concerned with processing methods of the measurement values of sensors in the control system. When some faults happen to sensor components, the measurement value of sensors cause the malfunction of the plant. So it is necessary to detect and reduce the influence of faults to control with reliability for the overall system. The sensor status must be always good for best demonstration of the controller performance. A self-validating sensor detects the sensor state from the measurement value, reconstruct a soft sensor and can improve reliability of the sensor. If sensor faults, the sensor is detected and reconstructed with the best estimate from its correlation to other sensors and historical data. It is applied to the control of a flexible link system with the sensor fault problems in the light sensor module for position to show the applicability. In this paper, we propose a digital controller which reduces deflection of the moving set-point by reconstructing output of a sensor when the sensor fault is detected.

  • PDF

Fragile Watermarking to detect change of small range on image (화상의 작은 영역 변화를 검출 가능한 연성 워터마킹)

  • Lee, Hye-Joo;Oh, Yun-Hee;Park, Ji-Hwan;Kim, Kwangjo
    • Proceedings of the Korea Multimedia Society Conference
    • /
    • 2000.11a
    • /
    • pp.493-497
    • /
    • 2000
  • Fragile watermarking is a technique far autoentication/integrity of digital data. Unlike robust watermarking, il has to design to be vulnerable against some slight processing to verify the modification of digital data. Feature of fragile watermarking is to identify the modifications of data and to locate some places modification occurred at the same time, so it has to identify slight changes of small range if possible. In this paper, fragile watermarking is proposed that the changes of small range on image can be identified using the watermark sequence with period and the values of low bit planes in an image.

  • PDF

Blind Watermarking Using DCT and Variance (DCT 및 분산을 이용한 블라인드 워터마킹)

  • Shin, Yong-Dal
    • Journal of Korea Multimedia Society
    • /
    • v.9 no.10
    • /
    • pp.1276-1281
    • /
    • 2006
  • In this paper, We proposed a robust blind digital watermarking algorithm using variance and DCT domain. The proposed method embedded watermark signals into DC components of $8{\times}8$ block DCT using valiance, texture regions and smooth regions. In the digital watermarking algorithms using DCT domain, more robustness can be achieved if watermarks are embedded in DC components since DC components have much larger perceptual capacity than AC components. Experiment showed that robustness of the proposed method better than that of the conventional methods in JPEG quality and scaling attack.

  • PDF

A Study on the Management of International Fishery Resources using Cooperative Game Theory (협조적 게임이론을 이용한 국가 간 수산자원관리에 관한 연구)

  • Choi, Jong-Du;Cho, Jung-Hee
    • Ocean and Polar Research
    • /
    • v.30 no.2
    • /
    • pp.173-180
    • /
    • 2008
  • This study demonstrates that cooperative management can provide more benefits than noncooperative management for Korea and Japan fishery. We have studied one management strategy, namely, fishing under joint maximization of net benefits in coastal waters of two countries, using a cooperative game theory. The present net return under non-cooperation amounts to 420,255 million won. However, if two countries cooperate one with another, this figure can get to 2,636,565 million won. We consider this to be an important conclusion as close management relationships have developed between the two countries since the establishment of the EEZ in 1996. The results of the study can also help balance resource conservation and the appropriate catch quota in each country.

A Study on the Security Technology of the Location based Tourism Information Service (위치 기반 관광 정보 서비스 보안 기술 연구)

  • Kim, Taekyung
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.12 no.2
    • /
    • pp.25-29
    • /
    • 2016
  • Owing to the change of economic trends, the importance of the tourism industry is growing more and more. In particular, the number of foreign tourists continues to increase and the type of tourists is being changed into FIT (Foreign Independent Traveler). Therefore it is an important issue to provide the effective information to foreign tourists. To solve these problems, a variety of IT technology is being used in the tourism information systems. Especially the location based tour information service is being emerged. This kinds of tourism information service is a type of LBS (Location Based Services). But if the security of the location based tourism information service is not guaranteed, it can lead to many dangers. In this paper, the trends of location based tourism information service are surveyed. Also the security threats and countermeasures for the location based tourism information service are analyzed. This paper suggests secret considerations for the location based tourism information service.