• Title/Summary/Keyword: Internal Buffer

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Dynamic-Response-Free SMPS Using a New High-Resolution DPWM Generator Based on Switched-Capacitor Delay Technique (Switched-Capacitor 지연 기법의 새로운 고해상도 DPWM 발생기를 이용한 Dynamic-Response-Free SMPS)

  • Lim, Ji-Hoon;Park, Young-Kyun;Wee, Jae-Kyung;Song, In-Chae
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.49 no.1
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    • pp.15-24
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    • 2012
  • In this paper, we suggest the dynamic-response-free SMPS using a new high-resolution DPWM generator based on switched-capacitor delay technique. In the proposed system, duty ratio of DPWM is controlled by voltage slope of an internal capacitor using switched-capacitor delay technique. In the proposed circuit, it is possible to track output voltage by controlling current of the internal capacitor of the DPWM generator through comparison between the feedback voltage and the reference voltage. Therefore the proposed circuit is not restricted by the dynamic-response characteristic which is a problem in the existing SMPS using the closed-loop control method. In addition, it has great advantage that ringing phenomenon due to overshoot/undershoot does not appear on output voltage. The proposed circuit can operate at switching frequencies of 1MHz~10MHz using internal operating frequency of 100 MHz. The maximum current of the core circuit is 2.7 mA and the total current of the entire circuit including output buffer is 15 mA at the switching frequency of 10 MHz. The proposed circuit has DPWM duty ratio resolution of 0.125 %. It can accommodate load current up to 1 A. The maximum ripple of output voltage is 8 mV. To verify operation of the proposed circuit, we carried out simulation with Dongbu Hitek BCD $0.35{\mu}m$ technology parameter.

Design of ATM Switch-based on a Priority Control Algorithm (우선순위 알고리즘을 적용한 상호연결 망 구조의 ATM 스위치 설계)

  • Cho Tae-Kyung;Cho Dong-Uook;Park Byoung-Soo
    • The Journal of the Korea Contents Association
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    • v.4 no.4
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    • pp.189-196
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    • 2004
  • Most of the recent researches for ATM switches have been based on multistage interconnection network known as regularity and self-routing property. These networks can switch packets simultaneously and in parallel. However, they are blocking networks in the sense that packet is capable of collision with each other Mainly Banyan network have been used for structure. There are several ways to reduce the blocking or to increase the throughput of banyan-type switches: increasing the internal link speeds, placing buffers in each switching node, using multiple path, distributing the load evenly in front of the banyan network and so on. Therefore, this paper proposes the use of recirculating shuffle-exchange network to reduce the blocking and to improve hardware complexity. This structures are recirculating shuffle-exchange network as simplified in hardware complexity and Rank network with tree structure which send only a packet with highest priority to the next network, and recirculate the others to the previous network. after it decides priority number on the Packets transferred to the same destination, The transferred Packets into banyan network use the function of self routing through decomposition and composition algorithm and all they arrive at final destinations. To analyze throughput, waiting time and packet loss ratio according to the size of buffer, the probabilities are modeled by a binomial distribution of packet arrival. If it is 50 percentage of load, the size of buffer is more than 15. It means the acceptable packet loss ratio. Therefore, this paper simplify the hardware complexity as use of recirculating shuffle-exchange network instead of bitonic sorter.

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Effect of Ethanol and/or Organic Acids on the Growth of Lactobacillus plantarum, Leuconostoc mesenteroides, Kluyveromyces marxianus Identified from Mul-kimchi (물김치 서식 미생물, Lactobacillus plantarum, Leuconostoc mesenteroides, Kluyveromyces marxianus 생육에 Ethanol과 유기산이 미치는 영향)

  • 한영숙
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.5
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    • pp.425-432
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    • 2003
  • Effects of ethanol and/or some organic acid on the growth of some microorganism grown in Kimchi, Lactobacillus plantarum, Leuconostoc mesenteroides. Kluyveromyces marxianus, were identified and the cell injury was observed by measuring optical density at 260nm. When 0.0∼5.0% ethanol was added in the growth medium, the cell growth was inhibited depending on the concentration. Organic acids involving acetic, adipic and citric acid inhibited the growth of L. plantarum and Leu. mesenteroides, but K. marxianus, the yeast, was not at 0.1% of organic acid. When 2.0% of ethanol and 0.1% of organic acid were used, adipic acid was more effective on the growth inhibition. This inhibition of microbial growth seemed to be caused by the leakage of internal contents from microbes which were observed by the optical density at 260nm in the buffer supernatant. 5.0% of ethanol accelerated the optical density increase at 260nm in L. plantarum, Leu. mesenteroides and K. marxianus, but 2.0% of ethanol did not. 0.1% organic acid increased the absorbance of the supernatant in lactic bacteria, but not in yeast, K. marxianus. The measurement of absorbance at 260nm revealed that the cell injury increased when 2.0% of ethanol and/or 0.1% of organic acid. especially adipic acid were added.

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Use of Real-Time PCR and Internal Standard Addition Method for Identifying Mixed Ratio of Chicken Meat in Sausages (Real-Time PCR과 Internal Standard Addition법을 이용한 돼지고기 소시지에 혼합된 닭고기의 정량)

  • Lee, Namrye;Joo, Jae-Young;Yeo, Yong-Heon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.9
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    • pp.1097-1105
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    • 2017
  • This study examined how much chicken meat was in sausage made with pork. Both real-time polymerase chain reaction (PCR) and internal standard addition were used. Fifty ng of chicken DNA was added to the sausages as an internal standard. The addition of standard DNA increased the amplification efficiency of PCR and confirmed the possibility of quantitative analysis. A QIAamp DNA Micro Kit was used to improve the DNA recovery and amplification efficiency. The density of template DNA and primer were suitable for $3.0{\sim}5.0{\mu}L$ and $0.5{\mu}L$, respectively. Each DNA of pig and chicken was diluted in 10-fold from steps 50 ng to 0.05 ng. The detection limit of both pig and chicken meat was more than 0.05 ng and the correlation coefficient of the standard curve was at least 0.98. The result of the quantitative analysis after heat treatment of 3 samples of pigs and chickens mixed at 70:30 showed a 5.7% difference (64.3:35.7) between the expected value and measured value. The quantitative value was changed by affecting the DNA according to the heat treatment ($70^{\circ}C$, 10 min). An analysis of the pork and chicken content in sausages showed that it was difficult to detect chicken meat and the quantitative value of DNA according to the Ct value was very low. On the other hand, when adding standard material (50 ng of chicken DNA) to the sausages, the Ct value decreased gradually with increasing chicken mixing ratio. Thus, the mixing ratio of chicken in sausages could be estimated.

Preparation of a Liquid Membrance Type Ion-Selective Electrode and Its Application to the Potentiometric Titration (액체막형 구리이온 선택성 전극의 제작과 전위차적정에의 응용)

  • Heung Lark Lee;Seung Tae Yang
    • Journal of the Korean Chemical Society
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    • v.29 no.2
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    • pp.137-143
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    • 1985
  • Construction of a liquid membrane type of cupric ion selective electrode and its application to the potentiometric titration have been studied. A liquid ion-exchange membrance was prepared by extracting Cu(II) in aqueous solution into 1-(2-pyridylazo)-2-naphthol/nitrobenzene. A Ag/AgCl internal reference electrode was dipped into the aqueous reference solution of $1.00 {\times} 10^{-3}M\;Cu(NO_3)_2$ buffered with HAc-NaAc buffer solution, which was in contact with the nitrobenzene extract. The electrode showed the nernstian response to Cu(II) in the concentration range from $1.00{\times} 10^{-6}$ to $1.00{\times} 10^{-3}$M. The most suitable ion-exchanger concentration in the liquid membrane was $1.00{\times} 10^{-4}$M. The selectivity coefficients of the electrode for the various metal cations were investigated. The electrode was applied to the potentiometric titration of Cu(II) with EDTA.

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An Efficient H.264/AVC Entropy Decoder Design (효율적인 H.264/AVC 엔트로피 복호기 설계)

  • Moon, Jeon-Hak;Lee, Seong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.12
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    • pp.102-107
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    • 2007
  • This paper proposes a H.264/AVC entropy decoder without embedded processor nor memory fabrication process. Many researches on H.264/AVC entropy decoders require ROM or RAM fabrication process, which is difficult to be implemented in general digital logic fabrication process. Furthermore, many researches require embedded processors for bitstream manipulation, which increases area and power consumption. This papers proposes hardwired H.264/AVC entropy decoder without embedded processor, which improves data processing speed and reduces power consumption. Furthermore, its CAVLC decoder optimizes lookup table and internal buffer without embedded memory, which reduces hardware size and can be implemented in general digital logic fabrication process without ROM or RAM fabrication process. Designed entropy decoder was embedded in H.264/AVC video decoder, and it was verified to operate correctly in the system. Synthesized in TSMC 90nm fabrication process, its maximum operation frequency is 125MHz. It supports QCIF, CIF, and QVGA image format. Under slight modification of nC register and other blocks, it also support VGA image format.

Hardware Architecture and its Design of Real-Time Video Compression Processor for Motion JPEG2000 (Motion JPEG2000을 위한 실시간 비디오 압축 프로세서의 하드웨어 구조 및 설계)

  • 서영호;김동욱
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.1
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    • pp.1-9
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    • 2004
  • In this paper, we proposed a hardware(H/W) structure which can compress and recontruct the input image in real time operation and implemented it into a FPGA platform using VHDL(VHSIC Hardware Description Language). All the image processing element to process both compression and reconstruction in a FPGA were considered each of them was mapped into a H/W with the efficient structure for FPGA. We used the DWT(discrete wavelet transform) which transforms the data from spatial domain to the frequency domain, because use considered the motion JPEG2000 as the application. The implemented H/W is separated to both the data path part and the control part. The data path part consisted of the image processing blocks and the data processing blocks. The image processing blocks consisted of the DWT Kernel for the filtering by DWT, Quantizer/Huffman Encoder, Inverse Adder/Buffer for adding the low frequency coefficient to the high frequency one in the inverse DWT operation, and Huffman Decoder. Also there existed the interface blocks for communicating with the external application environments and the timing blocks for buffering between the internal blocks. The global operations of the designed H/W are the image compression and the reconstruction, and it is operated by the unit or a field synchronized with the A/D converter. The implemented H/W used the 54%(12943) LAB(Logic Array Block) and 9%(28352) ESB(Embedded System Block) in the APEX20KC EP20K600CB652-7 FPGA chip of ALTERA, and stably operated in the 70MHz clock frequency. So we verified the real time operation. that is. processing 60 fields/sec(30 frames/sec).

Determination of 8-iso-PGF as Oxidative Stress Marker in Human Urine by High Performance Liquid Chromatography with Tandem Mass Spectrometry (LC/MS/MS를 이용한 산화성 스트레스 지표로써 소변 중 8-iso-PGF 분석)

  • Kho, Young-Lim;Lee, Eun-Hee;Chae, Hong-Jae;Choi, Kyung-Ho;Paik, Do-Myung
    • Journal of Environmental Health Sciences
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    • v.36 no.1
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    • pp.44-51
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    • 2010
  • This study aimed to develop analytical method for 8-isoprostanes as biomarkers for oxidative stress with LC/MS/MS technique and to apply the method for human urine samples. Analyzed compounds for urinary oxidative stress markers were 7 stereo-isomers of prostaglandins and the internal standard (iso-$PGF_{2{\alpha}}-d_4$) was used to adjust the recovery rate. The method for determining urinary iso-$PGF_{2{\alpha}}$ consisted of solid phase extraction and LC/MS/MS detection. Separation of isomers of prostaglandins completed by porous graphitic carbon column and buffer solution. Detection limits for urinary markers of oxidative stress, iso-$PGF_{2{\alpha}}$ with LC/MS/MS were 0.01 ng/ml by S/N ratio 3 and 0.028 ng/ml by calculated as to FDA method. The recovery (92.8~101.9%) and precision (8.8~20.7%) of analysis were feasible for detecting iso-$PGF_{2{\alpha}}$ in real human urine samples. We detected 4 isomers of prostaglandins in human urine samples. Mean (standard deviation) of urinary iso-$PGF_{2{\alpha}}$ concentration were 0.231 (0.117) ng/mg creatinine for smoking group and 0.154 (0.082) ng/mg creatinine for non-smoking group.

A Recombinant Human GM-CSF Protein Expressed as an Inclusion form in Escherichia coil Stimulates Colony Formation and Cell Proliferation in vitro

  • Lee, Ah-Young;Kim, Jin-Kyoo;Chung, Hye-Kyung;Bae, Eun-Kong;Hwang, Hung-Suk;Han, Jae-Yong;Lee, Choon-Taek;Hong, Soon-Kwnag;Youn, Hyun-Joo
    • Journal of Microbiology
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    • v.40 no.1
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    • pp.77-81
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    • 2002
  • Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a pleiotropic hematspoietic growth factor involved in the development of myeloid cells from bone marrow, and an activator of mature myeloid cells functioning in a variety of antimicrobial and inflammatory responses. Recently, recombinant GM-CSF is increasingly under clinical study for treatment of various diseases including cancer, infectious diseases and hematopoietic diseases as well as for an immune response modulator, In this study, we constructed a recombinant human GM-CSF (rhGM-CSF) expression plasmid with a pelB leader sequence and His. Tag under T7 promoter control. The expression construct was shown to produce a recombinant protein of 20 kDa in the 8M urea preparation, indicating the rhGM-CSF may be expressed as an insoluble inclusion form. The 20 kDa recombinant protein in 8M urea was transformed into the water-so1ub1e form by dialysis against PBS buffer (phosphate buffered saline). The soluble rhGM-CSF protein was shown to stimulate colony formation and cell proliferation in vitro, indicating that the rhGM-CSF could be refolded into its native form to show colony stimulating activity.

Implementation and performance evaluation of SS No.7 in B-ISDN networks (B-ISDN 망에서 공통선 신호 기능의 구현 및 성능 평가)

  • Rhee, Woo-Seop;Kim, Hwa-Suk;An, Yoon-Young;Kwon, Yool
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.5
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    • pp.1397-1408
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    • 1998
  • Service networks for the future communication networks will be combined by the B-ISDN networks. These service networks also will use SS No.7 as the signaling transport network for the control of user requriement service. Therefore, ITU-T recommended B-ISDN signaling layers for SS No.7 as a substitute for N-ISDN MTP signaling layer. In this paper, we propose the implementation structure and describe the characteristics and functions of each signaling layer of SS No.7, which are adapted to ATM switching system, and evaluate a performance. The structure of SSCOP transmission buffer using a linked list and an unit frame length is proposed for SAAL layer and the implementation structure and internal routing method according to the ATM switching system are also proposed for MTP-3b layer. Additionally, we propose the ISUP/B-ISUP level interworking structure using only associated mode, which are presented in the first stage of B-ISDN as the effective internatworking structure of SS No.7 for the circuit related signaling network between the existing N-ISDN networks and B-ISDN networks.

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