초고온성 고세균 Thermococcus onnurineus의 개미산으로부터 바이오수소 생산을 위한 통계적 배지 최적화

이성목,김태완,이현숙,이정현,강성균 한국해양과학기술원 2017 Ocean and Polar Research Vol.39 No.4

Medium compositions for the hyperthermophilic archaeon, Thermococcus onnurineus NA1 was statistically optimized to enhance formate-driven hydrogen (H2) production by using response surface methodology. From the Plackett-Burman design-based experiment, it was confirmed that among the minor components of medium such as KCl, MgSO4, NH4Cl, Cystein-HCl, trace elements, Fe-EDTA and CaCl2, the trace elements were screened as the only positively effective components with respect to H2 production. Subsequently, the optimal concentrations of the trace elements and the major components of a medium such as NaCl, yeast extract and sodium formate were determined from the five-level central composite design (CCD)-based experiment. The resulting quadratic model predicted the maximum H2 production of 46.6 mmol/L in serum bottle and it was validated experimentally using the optimal medium initially supplemented with 26.70 g/L of NaCl, 9.81 g/L of sodium formate, 3.50 g/L of yeast extract and 4.59 mL/L of trace elements. From the duplicate batch cultivations in the fermentor using the optimized medium, the a maximum H2 production rate up to 71.8 mmol/L/h could be obtained, which was a 65% enhanced value compared with that obtained using the control medium, showing the high efficiency of the optimized medium.

Fault diagnosis of partial rub and looseness in rotating machinery using Hilbert-Huang transform

이성목,최연선 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.11

Partial rub and looseness are common faults in rotating machinery because of the clearance between the rotor and the stator. These problems cause malfunctions in rotating machinery and create strange vibrations coming from impact and friction. However, non-linear and non-stationary signals due to impact and friction are difficult to identify. Therefore, exact time and frequency information is needed for identifying these signals. For this purpose, a newly developed timefrequency analysis method, HHT (Hilbert-Huang Transform), is applied to the signals of partial rub and looseness from the experiment using RK-4 rotor kit. Conventional signal processing methods such as FFT, STFT and CWT were compared to verify the effectiveness of fault diagnosis using HHT. The results showed that the impact signals were generated regularly when partial rub occurred, but the intermittent impact and friction signals were generated irregularly when looseness occurred. The time and frequency information was represented exactly by using HHT in both cases, which makes clear fault diagnosis between partial rub and looseness.

JPEG2000 Encoder를 위한 EBCOT Tier-1의 하드웨어 구현

이성목,장원우,조성대,강봉순,Lee, Sung-Mok,Jang, Won-Woo,Cho, Sung-Dae,Kang, Bong-Soon 한국융합신호처리학회 2010 융합신호처리학회 논문지 (JISPS) Vol.11 No.2

본 논문은 JPEG2000 Encoder를 위한 EBCOT Tier-1의 하드웨어 구현에 관한 것이다. 2000년대 초반, JPEG의 단점을 극복하기 위해 차세대 정지영상 압축 표준으로 등장한 것이 JPEG2000이다. JPEG2000 표준은 DWT(Discrete Wavelet Transform)과 EBCOT Entropy coding 기술을 기반으로 하고 있다. 이 중 EBCOT(Embedded block coding with optimized truncation)은 JPEG2000 표준에서 실제 압축을 수행하는 가장 중요한 기술 중 하나이다. 하지만 EBCOT는 Bit-level 처리를 하기 때문에 JPEG2000 압축 과정 중 절반 정도의 연산 시간을 차지하는 단점을 가지고 있다. 그래서 이에 본 논문은 EBCOT 연산의 효율성을 높이기 위해 수정된 Context 추출 방법과 산술 부호화기 MQ- Coder를 하드웨어 구현하였다. 제안된 시스템은 Verilog-HDL로 구현되었으며 TSMC 0.25um ASIC 라이브러리로 합성한 결과, 게이트 카운트는 30,511개로 구현되었으며, 50MHz의 동작 조건을 만족한다. This paper presents the implementation of a EBCOT TIER-1 for JPEG2000 Encoder. JPEG2000 is new standard for the compression of still image for overcome the artifact of JPEG. JPEG2000 standard is based on DWT(Discrete Wavelet Transform) and EBCOT Entropy coding technology. EBCOT(Embedded block coding with optimized truncation) is the most important technology that is compressed the image data in the JPEG2000. However, EBCOT has the artifact because the operations are bit-level processing and occupy the harf of the computation time of JPEG2000 Compression. Therefore, in this paper, we present modified context extraction method for enhance EBCOT computational efficiency and implemented MQ- Coder as arithmetic coder. The proposed system is implemented by Verilog-HDL, under the condition of TSMC 0.25um ASIC library, gate counts are 30,511EA and satisfied the 50MHz operating condition.

NTSC/PAL/SECAM 표준을 만족하는 Variable-clock Video Encoder의 내부 필터 설계

이성목,김주현,강봉순 東亞大學校附設 情報技術硏究所 2005 情報技術硏究所論文誌 Vol.13 No.1

In this paper, we present the design of the filters for variable-clock video encoder in CCTV system The SONY corporation preoccupies 80% of the CCD market in CCTV application. But, SONY corporation's CCD module used in CCTV requires particular clock frequency. Generally, a video encoder is operated 27MHz sampling frequency. That is clock frequency of video encoder different with CCD's clock frequency. If we used a filter of general video encoder, filter's characteristics are changed and don't be satisfied with standard. So, we design the filters that satisfied with TV broadcasting standards without regard to clock frequency. The proposed filters are simulated by using the MATLAB. This paper also proposes the variable-clock encoder that can be activated at the clock equal to the CCD clock without the scaler and the PLL.

Effect of sludge treatment on biogas production from Saccharina japonica ethanol fermentation by-products

이성목,이재화 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

The brown seaweed contained various carbohydrates, such as alginate, laminaran, and mannitol. However, the production of pure culture that utilized carbohydrates was extremely limited. A mixedculture produces better results for digestion than does a pure culture. The aim of this study was todetermine the level of biogas production from by-products of Saccharina japonica using a sludgepretreatment with an optimal pH. A freeze pretreatment was found to produce a better result than heatand ultrasonic irradiation pretreatments, and the optimal initial pH for biogas production was 8.

두근두근 해적 룰렛 외 1편

이성목 심미안 2015 문학들 Vol.- No.39

K-ary n-cubes에서 가상채널을 사용한 적응적 웜홀 라우팅

이성목 부경대학교 기초과학연구소 1998 부경대 기초과학연구논문집 Vol.1 No.-

Formulation of a Low-cost Medium for Improved Cost-effectiveness of Hydrogen Production by Thermococcus onnurineus NA1

이성목,이정민,이성혁,김재영,이현숙,강성균 한국생물공학회 2019 Biotechnology and Bioprocess Engineering Vol.24 No.5

Hydrogen has been receiving considerable attention as a clean energy carrier. Thermococcus onnurineus NA1, a hyperthermophilic archaeon, is capable of producing hydrogen using carbon monoxide (CO) in a growthassociated manner, providing a promising platform to upcycle industrial waste gases. In order to improve costeffectiveness of the biological hydrogen production from carbon monoxide (CO), we developed formulation of a low-cost medium for T. onnurineus 156T by substituting fishmeal and sea salt for yeast extract (YE) and reagentgrade salts, respectively. In serum bottle cultures, hydrogen production by the 156T strain was less than 30% in fishmeal-containing media when compared to that of the YE-containing MM1 medium. However, hydrogen production was increased substantially by adaptive evolution in the fishmeal-sea salt (FMSS) medium. In bioreactor experiments, the resulting strain 156T-FA showed shorter lag phase and 70% higher maximum hydrogen production rate in FMSS medium than the parent strain 156T. Our results showed that the H2 production cost was reduced by ca. 95%, when YE and chemical salts were replaced by fishmeal and sea salt, respectively.

휴대디지털 기기를 위한 소형화된 TV-out 비디오 프로세서의 구현

이성목,장원우,하주영,김주현,강봉순,Lee, Sung-Mok,Jang, Won-Woo,Ha, Joo-Young,Kim, Joo-Hyun,Kang, Bong-Soon 한국융합신호처리학회 2006 융합신호처리학회 논문지 (JISPS) Vol.7 No.4

본 논문은 TV 출력 기능이 필요한 휴대용 디지털 기기를 위한 소형화된 비디오 프로세서의 구현에 관한 것이다. 설계된 비디오 프로세서는 ITU-R(International Telecommunication Union-Radiocomunication) BT.470 표준을 모두 지원한다. 또한 설계된 시스템의 하드웨어 부담을 줄여 다양한 디지털 기기에 적용하기 위해 하드웨어 사이즈를 소형화 하는데 설계에 중점을 두었다. ITU-R BT.470 표준은 크게 NTSC, PAL, SECAM의 3가지로 구분되는데, NTSC와 PAL은 색차 신호를 전송하기 위해서 구조진폭변조(QAM)를 사용하고, SECAM은 주파수변조(FM)를 사용한다. SECAM 표준은 변조를 위해 pre-emphasis 필터와 anti-cloche 필터가 필요한데, 표준(ITU-R BT.470)에서 권장하는 anti-cloche 필터의 특성이 아주 예리해서 디지털로 설계하기가 용이하지 않다. 이에 본 논문에서는 anti-cloche 필터의 특성을 설계하기 쉽도록 바꾸고, 표준에서 요구하는 결과와 동일하도록 수정된 변조 방법을 제안한다. 각종 휴대용 디지털 기기는 내장 배터리로 동작되므로 소비전력을 줄이기 위하여 출력모드에 따른 파워소비를 가변하도록 하였다. 제안된 비디오 프로세서는 Altera사의 FPGA APEX20K1000EBC652-3과 삼성 LCD-TV를 이용하여 실시간 검증을 수행하였다. This paper presents the design and implementation of a video processor for the device of need TV-OUT function. The designed video processor satisfies the standard conditions of ITU-R(International Telecommunication Union-Radiocommunication) BT.470. Also, in order to apply various digital device, we concentrate upon hardware complexity. ITU-R BT.470 can be classified as NTSC, PAL or SECAM. NTSC and PAL use QAM(Quardarature Amplitude Modulation) to transmit color difference signals and SECAM uses FM(Frequency Modulation). FM must have antic-cloche filter but filter recommended by ITU-R BT.470 is not easy to design due to sharpness of the frequency response. So this paper proposes that the special quality of anti-cloche filter is transformed easy to design and the modulation method is modified to be identical with the result required at standard. The processor can control power consumption by output mode to apply portable digital devices. The proposed processor is experimentally demonstrated with ALTERA FPGA APEX20KE EP20K1000EBC652-3 device and SAMSUNG LCD-TV.

구두 시대

이성목 고요아침 2014 열린시학 Vol.19 No.4