• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.35-44
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• 2006

Reflective semiconductor optical amplifiers(R-SOAs) were designed with high gain, wide optical bandwidth, high thermal reliability and wide modulation bandwidth in TO-can package for the transmitter of wavelength division multiplexed-passive optical network(WDM-PON) application. Double trench structure and current block layer were introduced in designing the active layer of R-SOA to enable high speed modulation. The injection power requirement and the viable temperature range of WDM-PON system are experimentally analysed in based on Amplified Spontaneous Emission(ASE)-injected R-SOAs. The effect of the different injection spectrum in the gain-saturated R-SOA was experimentally characterized based on the measurements of excessive intensity noise, Q factor, and BER. The proposed spectral pre-composition method reduces the bandwidth of injection source below the AWG bandwidth and thereby avoids spectrum distortion impeding the intensity noise reduction originated from the amplitude squeezing.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06b
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• pp.101-106
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• 2007

본 논문에서는 SOA(Service Oriented Architecture) 기반으로 국가 R&D 정보의 종합 조회 기능을 제공하는 국가 R&D 정보시스템(RnDIS: R&D Information System)을 설계 및 구현하였다. 물리적으로 분산되고 각각 별도의 DB를 구성하여 활용하는 이질적인 4개의 응용시스템의 기능을 효과적으로 연계 및 활용하기 위해 유연하며 확장이 용이한 SOA를 채택하였다. 서비스의 식별, 정의, 분석 등의 개발을 위해 CBD 방법론을 확장한 새로운 서비스 개발방법론을 정의 및 활용하였으며, RnDIS를 위해 4개의 어플리케이션 서비스와 4개의 비즈니스 프로세스 서비스를 정의 및 설계하였다. 어플리케이션 서비스는 기존의 자바코드로부터 WSDL(Web Service Description Language)을 생성하는 래핑(wrapping) 방식을 사용하여 구현하였며, 비즈니스 프로세스 서비스는 BPEL(Business Process Execution Language) 엔진을 이용하여 어플리케이션 서비스를 조합하는 방식을 이용하여 구현하였다. RnDIS는 NTIS(National Science and Technology Information System) 공식 홈페이지(http://www.ntis.go.kr)의 종합검색 메뉴로 시범서비스 되고 있으며, 향후 서비스 대상 데이터의 확장과 기능 추가를 통해 정식 서비스를 오픈 할 예정이다.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.388-389
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• 2009

• Korean Journal of Optics and Photonics
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• v.11 no.5
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• pp.340-346
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• 2000

Traveling wave type semiconductor optical amplifiers integrated with spot-size-converter (SSC-TW-SOA) have been extensively studied for the improvement of coupling effiClency With single-mode fiber and fO! the cost reducClon 111 a packaging In tlIis paper the slructural dependence of the spot-slZe-converter on the effective facet reflectlvllY $R_{eff}$ was experimentally as well as thcoretienlly mvestlgated. It was shown that not only a sufficient mode-conversion in a sse region along the latersl and tran~verse directions but also an introductIOn of angled-facet were very essential in order to reduce $R_{eff}$ Very small ripple less than 0.1 dB in an amplified spontaneous emission spectrum was observed with the fabncated SSC-lW-SOA which consists of the wrndow length of $20\mu\textrm{m}$, facet angle of $7^{\circ}$, and antlrelleetioll-coated facet of ] % reflectivity.tivity.

• Korean Journal of Optics and Photonics
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• v.14 no.5
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• pp.509-514
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• 2003

Mach-Zehnder interferometric wavelength converters with monolithically integrated semiconductor optical amplifiers (SOA's) have been fabricated and characteristics of wavelength conversion at 10 Gb/s have been investigated for wavelength span of 40 nm. The devices have been achieved by using a butt-joint combination of buried ridge structure type SOA's and passive waveguides. In the integration, a new method has been applied that removes p+InP cladding layer leading to high propagation loss and forms simultaneously the current blocking and the cladding layer using undoped InP. The module packaging has been achieved by using a titled fiber array for effective coupling into the tilted waveguide in the wavelength converter. Using the module, wavelength conversion with power penalty lower than 1 ㏈ at 10 Gb/s has been demonstrated for wavelength span of 40 nm. In addition, it is show that the module can provide 2R (re-amplification, re-shaping) operation by demonstrating the conversion with the negative penalty.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.5
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• pp.1135-1142
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• 2000

In this study, we fabricated a 1.55um polarization-insensitive semiconductor optical amplifier(SOA) with rectangular buried heterostructure using a InGaAsP/InP double heterostructure wafer. Measured characteristics of the fabricated SOA are that 3dR bandwidth is 35nm and 3dB saturation output power is 4dBm. Maximum gain under the 150mA CW driving condition is 19.4dB. We measured the ASE(amplified spontanouse emission) Power spectrum or n and TM mode in the fabricated SOA using ASE measurement system and knew that distributions of the TE and TM mode about the maxinum region are nearly coincident. this shows the fabricated SOA is a polarization-insensitive.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2A
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• pp.202-208
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• 2010

The performance of upstream transmission in SCM-PON is generally limited by the presence of OBI which is caused by the beating of two or more lasers. In this paper, we propose a novel approach for reducing OBI problem by using heterodyne detection with an additional LD as a local oscillator, resulting that the RF signal is shifted to the other spectal band. In addition, it is possible that the proposed method can provide the cost-effective solution thanks to the loop-back mechanism using R-SOA in ONUs. The performance is superior when the spectral width of LD is smaller and the power difference between the transmission LD and the oscillation LD is bigger. System configuration and design consideration are discussed. Performance of the systems is evaluated by simulator called OptSim. It is expected to provide WDM/SCM-PON system not only cost-effective but also efficient in increasing the number of subscribers.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1894-1901
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• 2015

A novel sulfatase gene, ary423 (1,536 bp ORF), encoding a protein of 511 amino acids with a calculated molecular mass of 56 kDa, was identified from Flammeovirga pacifica, which was isolated from deep-sea sediments of west Pacific Ocean. Amino acid sequence analysis revealed that Ary423 possessed a conserved C-X-A-X-R motif, which was recognized as the sulfatase signature. Phylogenetic analysis suggested that Ary423 belonged to arylsulfatases. After heterologous expression in Escherichia coli cells, the recombinant Ary423 was purified with a Ni⁺ affinity column, and was shown to be highly active at a broad range of temperatures from 30° to 70℃, with maximum activity at 40℃. Furthermore, recombinant Ary423 retained more than 70% and 40% of its maximum activity after 12 h of incubation at 50℃ and 60℃, respectively, exhibiting good thermostability at high temperatures. The optimal pH for Ary423 was determined to be 8.0 and the activity of Ary423 could be slightly enhanced by Mg²⁺. The recombinant enzyme could hydrolyze sulfate ester bonds in p-nitrophenyl sulfate (NPS) and Asparagus crude polysaccharides with a specific activity of 64.8 U/mg and 25.4 U/mg, respectively. These favorable properties could make Ary423 attractive for application in the desulfating process of agar production.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.353-354
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• 2008

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.1939-1946
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• 2009

Modern enterprise may be in need of developing the right application programs under rapidly changing business environment in fast time-to-market. But Most of enterprise without business process mechanism are very hard to develop the application needed in time when it will be changing their business. To solve this problem, we propose the business process framework based on the closed architecture. This approach is to develop the right application with reusing software modules in time and easily under rapid business process changing/improving through mapping BPM(Business Process Model), SOA(Service Oriented Architecture), and CBD(Component Based Development). we also define 5-Layers of BPF(Business Process Framework), and BNF(Backus Naur Form) for structuring BPF.