• Title/Summary/Keyword: 버퍼링

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Design of an 1.8V 6-bit 2GSPS CMOS ADC with an One-Zero Detecting Encoder and Buffered Reference (One-Zero 감지기와 버퍼드 기준 저항열을 가진 1.8V 6-bit 2GSPS CMOS ADC 설계)

  • Park Yu Jin;Hwang Sang Hoon;Song Min Kyu
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.6 s.336
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    • pp.1-8
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    • 2005
  • In this paper, CMOS A/D converter with 6bit 2GSPS Nyquist input at 1.8V is designed. In order to obtain the resolution of 6bit and the character of high-speed operation, we present an Interpolation type architecture. In order to overcome the problems of high speed operation, a novel One-zero Detecting Encoder, a circuit to reduce the Reference Fluctuation, an Averaging Resistor and a Track & Hold, a novel Buffered Reference for the improved SNR are proposed. The proposed ADC is based on 0.18um 1-poly 3-metal N-well CMOS technology, and it consumes 145mW at 1.8V power supply and occupies chip area of 977um $\times$ 1040um. Experimental result show that SNDR is 36.25 dB when sampling frequency is 2GHz and INL/DNL is $\pm$0.5LSB at static performance.

Analysis of Shadow Effect on High Resolution Satellite Image Matching in Urban Area (도심지역의 고해상도 위성영상 정합에 대한 그림자 영향 분석)

  • Yeom, Jun Ho;Han, You Kyung;Kim, Yong Il
    • Journal of Korean Society for Geospatial Information Science
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    • v.21 no.2
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    • pp.93-98
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    • 2013
  • Multi-temporal high resolution satellite images are essential data for efficient city analysis and monitoring. Yet even when acquired from the same location, identical sensors as well as different sensors, these multi-temporal images have a geometric inconsistency. Matching points between images, therefore, must be extracted to match the images. With images of an urban area, however, it is difficult to extract matching points accurately because buildings, trees, bridges, and other artificial objects cause shadows over a wide area, which have different intensities and directions in multi-temporal images. In this study, we analyze a shadow effect on image matching of high resolution satellite images in urban area using Scale-Invariant Feature Transform(SIFT), the representative matching points extraction method, and automatic shadow extraction method. The shadow segments are extracted using spatial and spectral attributes derived from the image segmentation. Also, we consider information of shadow adjacency with the building edge buffer. SIFT matching points extracted from shadow segments are eliminated from matching point pairs and then image matching is performed. Finally, we evaluate the quality of matching points and image matching results, visually and quantitatively, for the analysis of shadow effect on image matching of high resolution satellite image.

Analysis and solution to the phase concentration and DC-like component of correlation result in Daejeon correlator (대전 상관기의 상관 결과에 나타난 유사 DC 성분과 위상 집중 현상에 대한 원인 분석과 해결 방법)

  • Roh, Duk-Gyoo;Oh, Se-Jin;Yeom, Jae-Hwan;Oh, Chung-Sik;Jung, Jin-Seung;Chung, Dong-Kyu;Yun, Young-Joo;Oyama, Tomoaki;Ozeki, Kensuke;Onuki, Hirofumi
    • Journal of the Institute of Convergence Signal Processing
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    • v.14 no.3
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    • pp.191-204
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    • 2013
  • In this paper, we investigated the correlation outputs of Daejeon correlator at the viewpoints of the buffer memory setting related to the fine delay tracking and the under/overflow issue in FFT modules, in order to eliminate DC-like component and phase concentration to 0 degree. As the ring buffer memory is being used for the fine delay tracking, the DC-like component in correlation outputs is generated by improper setting of data read/write address, and then that address setting method is modified to exclude a polluted FFT segment in correlation processing when crossing the port/stream boundary. The phase concentration to 0 degree at beginning of bandpass is caused by inadequate scaling factors, which may be the origins of under/overflow occurred at internal computation of FFT stage. With the revised method of the ring buffer memory setting and the scaling factors in FFT, we could obtain higher signal-to-noise ratio and flux density, compared to the previous method, through the correlation processing of true observational data.

Multiplexing of UHDTV Based on MPEG-2 TS (MPEG-2 TS 기반의 UHDTV 다중화)

  • Jang, Euy-Doc;Park, Dong-Il;Kim, Jae-Gon;Lee, Eung-Don;Cho, Suk-Hee;Choi, Jin-Soo
    • Journal of Broadcast Engineering
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    • v.15 no.2
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    • pp.205-216
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    • 2010
  • In this paper, a method of MPEG-2 Transport Stream (TS) multiplexing for Ultra HDTV (UHDTV) and its design and implementation as a SW tool is described. In practice, UHD video may be divided into several HD videos and each video is encoded in parallel. Therefore, it is necessary to synchronize and multiplex multiple bitstreams encoding each HD video for transmitting and storing UHD video. In this paper, it is assumed that 4 HD videos partitioning a UHD spatially are encoded as H.264/AVC and two 5.0 channel audios are encoded by AC-3. Therefore, 4 H.264/AVC elementary streams (ESs) and 2 AC-3 ESs is mainly considered in the TS multiplexing of UHD. For the carriage of H.264/AVC and AC-3 over MPEG-2 TS, PES packetization and TS multiplexing are designed and implemented based on the extended specification of the MPEG-2 Systems and ATSC (Digital audio compressed standard), respectively. The implemented UHD TS multiplexing tool emulates real time HW operation in the time unit corresponding to the duration of one TS packet transmission in a given TS rate. In particular, in order to satisfy the timing model, the buffers defined in the TS System Target Decoder (T-STD) are monitored and their statuses are considered in the scheduling of TS multiplexing. For UHD multiplexing, two kinds of multiplexing structures, which are UHD re-multiplexing and UHD program multiplexing, are implemented and their strength and weakness are investigated. The developed UHD TS multiplexing tool is tested and verified in terms of the syntax and semantics conformance and functionalities by using a commercial analyzer and real-time presentation tools.

Phosphatidic Acid Production by PLD Covalently Immobilized on Porous Membrane (공유결합으로 다공성 막에 고정화된 PLD에 의한 포스퍼티딕산 생산)

  • Park, Jin-Won
    • Clean Technology
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    • v.21 no.4
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    • pp.224-228
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    • 2015
  • Phospholipase D (PLD) was immobilized on a submicro-porous membrane through covalent immobilization. The immobilization was conducted on the porous membrane surface with the treatment of polyethyleneimine, glutaraldehyde, and the anhydrase, in sequence. The immobilization was confirmed using X-ray photon spectrometer. The pH values of phosphatidylcholine (PC) dispersion solution with buffer were monitored with respect to time to calculate the catalytic activities of PC for free and immobilized PLD. The catalytic rate constant values for free PLD, immobilized PLD on polystyrene nanoparticles, and immobilized PLD on a porous cellulose acetate membrane were 0.75, 0.64, and 0.52 s-1, respectively. Reusability was studied up to 10 cycles of PC hydrolysis. The activity for the PLD immobilized on the membrane was kept to 95% after 10 cycles, and comparable to the PLD on the nanoparticles. The stabilities for heat and storage were also investigated for the three cases. The results suggested that the PLD immobilized on the membrane had the least loss rate of the activity compared to the others. From these studies, the porous membrane was feasible as a carrier for the PLD immobilization in the production of phosphatidic acid.

The Positional Accuracy Quality Assessment of Digital Map Generalization (수치지도 일반화 위치정확도 품질평가)

  • 박경식;임인섭;최석근
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.19 no.2
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    • pp.173-181
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    • 2001
  • It is very important to assess spatial data quality of a digital map produced through digital map generalization. In this study, as a aspect of spatial data quality maintenance, we examined the tolerate range of theoretical expectation accuracy and established the quality assessment standard in spatial data for the transformed digital map data do not act contrary to the digital map specifications and the digital map accuracy of the relational scale. And, transforming large scale digital map to small scale, if we reduce complexity through processes as simplification, smoothing, refinement and so on., the spatial position change may be always happened. thus, because it is very difficult to analyse the spatial accuracy of the transformed position, we used the buffering as assessment method of spatial accuracy in digital map generalization procedure. Although the tolerated range of generic positioning error for l/l, 000 and l/5, 000 scale is determined based on related law, because the algorithms adapted to each processing elements have different property each other, if we don't determine the suitable parameter and tolerance, we will not satisfy the result after generalization procedure with tolerated range of positioning error. The results of this study test which is about the parameters of each algorithm based on tolerated range showed that the parameter of the simplification algorithm and the positional accuracy are 0.2617 m, 0.4617 m respectively.

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Design of Experiment and Analysis Method for the Integrated Logistics System Using Orthogonal Array (직교배열을 이용한 통합물류시스템의 실험 설계 및 분석방법)

  • Park, Youl-Kee;Um, In-Sup;Lee, Hong-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.12
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    • pp.5622-5632
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    • 2011
  • This paper presents the simulation design and analysis of Integrated Logistics System(ILS) which is operated by using the AGV(Automated Guided Vehicle). To maximize the operation performances of ILS with AGV, many parameters should be considered such as the number, velocity, and dispatching rule of AGV, part types, scheduling, and buffer sizes. We established the design of experiment in a way of Orthogonal Array in order to consider (1)maximizing the throughput; (2)maximizing the vehicle utilization; (3)minimizing the congestion; and (4)maximizing the Automated Storage and Retrieval System(AS/RS) utilization among various critical factors. Furthermore, we performed the optimization by using the simulation-based analysis and Evolution Strategy(ES). As a result, Orthogonal Array which is conducted far fewer than ES significantly saved not only the time but the same outcome when compared after validation test on the result from the two methods. Therefore, this approach ensures the confidence and provides better process for quick analysis by specifying exact experiment outcome even though it provides small number of experiment.

Influence of the RF Power on the Optical and Electrical Properties of ITZO Thin Films Deposited on SiO2/PES Substrate (RF파워가 SiO2/PES 기판위에 증착한 ITZO 박막의 광학적 및 전기적 특성에 미치는 효과)

  • Choi, Byeong-Kyun;Joung, Yang-Hee;Kang, Seong-Jun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.3
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    • pp.443-450
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    • 2021
  • After selecting a PES substrate with excellent thermal stability and optical properties among plastic substrates, a SiO2 thin film was deposited as a buffer layer to a thickness of 20nm by plasma-enhanced chemical vapor deposition to compensate for the high moisture absorption. Then, the ITZO thin film was deposited by a RF magnetron sputtering method to investigate electrical and optical properties according to RF power. The ITZO thin film deposited at 50W showed the best electrical properties such as a resistivity of 8.02×10-4 Ω-cm and a sheet resistance of 50.13Ω/sq.. The average transmittance of the ITZO thin film in the visible light region(400-800nm) was relatively high as 80% or more when the RF power was 40 and 50W. Figure of Merits (ΦTC and FOM) showed the largest values of 23.90×10-4-1 and 5883 Ω-1cm-1, respectively, in the ITZO thin film deposited at 50W.

A Basic Study on the Establishment of Preservation and Management for Natural Monument(No.374) Pyeongdae-ri Torreya nucifera forest of Jeju (천연기념물 제374호 제주 평대리 비자나무 숲의 보존·관리방향 설정을 위한 기초연구)

  • Lee, Won-Ho;Kim, Dong-Hyun;Kim, Jae-Ung;Oh, Hae-Sung;Choi, Byung-Ki;Lee, Jong-Sung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.1
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    • pp.93-106
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    • 2014
  • In this study, Analyze environment of location, investigation into vegetation resources, survey management status and establish to classify the management area for Natural monument No.374 Pyengdae-ri Torreya nucifera forest. The results were as follows: First, Torreya nucifera forest is concerned about influence of development caused by utilization of land changes to agricultural region. Thus, establish to preservation management plan for preservation of prototypical and should be excluded development activity to cause the change of terrain that Gotjawal in the Torreya nucifera forest is factor of base for generating species diversity. Secondly, Torreya nucifera forest summarized as 402 taxa composed 91 familly 263 genus, 353 species, 41 varieties and 8 forms. The distribution of plants for the first grade & second grade appear of endangered plant to Ministry of Environment specify. But, critically endangered in forest by changes in habitat, diseases and illegal overcatching. Therefore, when establishing forest management plan should be considered for put priority on protection. Thirdly, Torreya nucifera representing the upper layer of the vegetation structure. But, old tree oriented management and conservation strategy result in poor age structure. Furthermore, desiccation of forest on artificial management and decline in Torreya nucifera habitat on ecological succession can indicate a problem in forest. Therefore, establish plan such as regulation of population density and sapling tree proliferation for sustainable characteristics of the Torreya nucifera forest. Fourth, Appear to damaged of trails caused by use. Especially, Scoria way occurs a lot of damaged and higher than the share ratio of each section. Therefore, share ratio reduction Plan should be considered through the additional development of tourism routes rather than the replacement of Scoria. Fifth, Representing high preference of the Torreya nucifera forest tourist factor confirmed the plant elements. It is sensitive to usage pressure. And requires continuous monitoring by characteristic of Non-permanent. In addition, need an additional plan such as additional development of tourism elements and active utilizing an element of high preference. Sixth, Strength of protected should be differently accordance with importance. First grade area have to maintenance of plant population and natural habitats. Set the direction of the management. Second grade areas focus on annual regeneration of the forest. Third grade area should be utilized demonstration forest or set to the area for proliferate sapling. Fourth grade areas require the introduced of partial rest system that disturbance are often found in proper vegetation. Fifth grade area appropriate to the service area for promoting tourism by utilizing natural resources in Torreya nucifera forest. Furthermore, installation of a buffer zone in relatively low ratings area and periodic monitoring to the improvement of edge effect that adjacent areas of different class.

A 0.31pJ/conv-step 13b 100MS/s 0.13um CMOS ADC for 3G Communication Systems (3G 통신 시스템 응용을 위한 0.31pJ/conv-step의 13비트 100MS/s 0.13um CMOS A/D 변환기)

  • Lee, Dong-Suk;Lee, Myung-Hwan;Kwon, Yi-Gi;Lee, Seung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.3
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    • pp.75-85
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    • 2009
  • This work proposes a 13b 100MS/s 0.13um CMOS ADC for 3G communication systems such as two-carrier W-CDMA applications simultaneously requiring high resolution, low power, and small size at high speed. The proposed ADC employs a four-step pipeline architecture to optimize power consumption and chip area at the target resolution and sampling rate. Area-efficient high-speed high-resolution gate-bootstrapping circuits are implemented at the sampling switches of the input SHA to maintain signal linearity over the Nyquist rate even at a 1.0V supply operation. The cascode compensation technique on a low-impedance path implemented in the two-stage amplifiers of the SHA and MDAC simultaneously achieves the required operation speed and phase margin with more reduced power consumption than the Miller compensation technique. Low-glitch dynamic latches in sub-ranging flash ADCs reduce kickback-noise referred to the differential input stage of the comparator by isolating the input stage from output nodes to improve system accuracy. The proposed low-noise current and voltage references based on triple negative T.C. circuits are employed on chip with optional off-chip reference voltages. The prototype ADC in a 0.13um 1P8M CMOS technology demonstrates the measured DNL and INL within 0.70LSB and 1.79LSB, respectively. The ADC shows a maximum SNDR of 64.5dB and a maximum SFDR of 78.0dB at 100MS/s, respectively. The ABC with an active die area of $1.22mm^2$ consumes 42.0mW at 100MS/s and a 1.2V supply, corresponding to a FOM of 0.31pJ/conv-step.