• 대한전자공학회논문지TC
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• 제44권12호
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• pp.63-72
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• 2007

본 논문은 기존의 E-PON 시스템에 TDM 의사회선 기능을 부가함으로써 데이터와 TDM 신호를 동시에 전달할 수 있는 시스템 개발에 관한 것이다. E-PON 기술은 FTTH를 구현할 수 여러 기술 중 하나이며, 저가의 이더넷 기술과 광 인프라를 결합한 차세대 액세스 네트워크 솔루션으로 대두되고 있다. TDM 의사회선 서비스는 패킷교환 네트워크를 통하여 기존의 TDM 회선교환 음성 및 데이터 트래픽을 전송할 수 있도록 해주는 새로운 음성/데이터 변환기술이다. 본 논문에서는 E-PON 시스템에 TDM 의사회선 서비스 모듈을 부가하고, QoS 제어 기능을 구현함으로써 QoS 손실 없이 데이터 및 TDM 서비스를 효율적으로 제공할 수 있다. 따라서 데이터와 TDM 신호가 동시에 전달될 수 있는 경쟁력 있는 시스템에 구축될 수 있다.

• 정보처리학회논문지D
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• 제8D권6호
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• pp.761-770
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• 2001

소프트웨어 산업이 급속하게 발전해감에 따라 정보 기술 업체간 경쟁이 더욱 심화되어 소프트웨어 재사용성, 적시성, 유지 보수성 등이 업체의 생명력으로 대두되면서 소프트웨어 컴포넌트 기술이 점차 각광을 받고 있다. 현재 몇몇 컴포넌트 생성 지원 도구들이 제공되고 있지만 컴포넌트의 식별, 모델링, 상세 설계, 코드 생성, 전개, 시험 등 컴포넌트 생성 전 과정을 밀접히 연계하여 지원하는 도구가 드물다. 또한, 특정 플랫폼에 의존적인 소규모 컴포넌트 생성에 중점을 두고 있어 사용자 관점의 다양한 규모의 컴포넌트 생성에는 제약이 따른다. 이 논문에서는 컴포넌트 생성에 연관된 모든 과정을 지원하는 컴포넌트 모델링 및 생성 지원 도구의 설계와 프로토타입 구현에 대해 기술한다. 컴포넌트 모델링은 영역 고유의 비즈니스 로직의 재사용 측면에서 컴포넌트 플랫폼 아키텍쳐에 관계없이 개념적인 컴포넌트의 식별 및 모델링을 지원한다. 상세설계 및 코드 생성 부분은 일차적으로 J2EE 플랫폼 아키텍쳐에 의존적으로 지원되며 설계 모델과 소스 코드의 일관성을 동적으로 유지시키는 Round-trip Engineering 기능을 지원한다.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.798-803
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• 1999

Prolyl endopeptidase [PEP; EC 3.4.21.26], a serine protease which is known to cleave peptide bonds on the carboxy side of a proline residue, plays an important role in the degradation of proline-containing neuropeptides that have been suggested to participate in learning and memory processes. An abnormal increase in the level of PEP, which can lead to generation of $A{\beta}$, is also suggested to be involved in Alzheimer's type senile dementia. In the course of screening PEP inhibitors from Basidiomycetes, the mushroom Polyozellus multiplex exhibited a high inhibitory activity against PEP. Two active compounds were isolated from the ethyl acetate soluble fraction by consecutive purification, using silica gel, Sephadex LH-20, and Lobar RP-18 chromatography. The chemical structures of these compounds were identified as thelephoric acid and 12-acety1-2,3,7,8-tetrahydroxy-[12H]-12-hydroxymethylbenzobis[I.2b,3.4b'] benzofuran-11-one (kynapcin-9) by spectral data including UV, IR, MS, HR-MS, $^1H-,{\;}^{13}C-$, and 2D-NMR. The $IC_{50}$ values of the thelephoric acid and kynapcin-9 were 0.157 ppm (446nM) and 0.087 ppm (212nM) and their inhibitor constants ($K_i$) were 0.73ppm ($2.09{\;}\mu\textrm{m}$) and 0.060 ppm (146 nM), respectively. Furthermore, they were non-competitive with a substrate in Dixon plots.

• 한국항공우주학회지
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• 제40권6호
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• pp.523-535
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• 2012

태양광 추진 항공기는 감시, 지구 모니터링, 통신 등에 대기 오염 없이 그리고 가까운 장래에 인공위성과의 가격 경쟁력까지 갖추게 될 수 있어 미래의 고고도 장기체공 임무수행을 위해 더욱더 그 중요성이 증대되고 있다. 그러나 전통적인 항공기 사이징 방법들은 태양광 추진 항공기에 바로 적용될 수 없다. 본 연구에서는 다양한 동력 시스템 구성품들이 태양광 추진 장기 체공 항공기의 사이징에 어떤 영향을 미치는지를 파악하기 위하여 에너지 균형 및 구속조건 연구를 수행하였다. 본 연구에서는 동력 생성과 연료전지의 재생 에너지 저장을 위한 광전지 모듈을 동력 시스템 구성품으로 고려하였다. 또한 본 연구 결과를 검증하기 위해 고고도 무인기에 이 새로운 사이징 기법을 적용하여 결과를 제시하였다.

• 한국IT서비스학회지
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• 제9권2호
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• pp.43-72
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• 2010

The Korean mobile telecommunication service market is faced with a tremendous competitive period, in which the market is entering into the maturity stage with launching of the 3rd generation service and with introduction of mobile number portability. In general, it is more important to sustain the old customers than to attracting new customers, as the life cycle of an industry is entering the maturity stage in which the growth rate of new customers is decreasing gradually or becoming stagnant. Until now, many researches had tested whether the customer satisfaction and loyalty were the core factors of sustaining customers or not. Also service quality and switching cost were given a remarkable attention for their possibility of exogenous factors, which could exercise effects to customer satisfaction and loyalty. In the same context, mobile telecommunication business has to seek a way to maintain the existing customers instead of promoting new customers. So this study investigates whether the service quality and switching barrier of mobile telecommunication could have effects on the customer satisfaction and loyalty, which are recognized as an efficient means to sustain the current customers. In order to test the hypothesis on the effects of service quality and switching barrier of mobile telecommunication to customer satisfaction and loyalty in Korean telecommunication industry, this study collected the questionnaire response data of students including middle and high school students and undergraduates, who are regarded as the major customers in that mobile telecommunication industry.

• Journal of Information Processing Systems
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• 제6권1호
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• pp.1-20
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• 2010

Due to the convergence of voice, data, and video, today's telecom operators are facing the complexity of service and network management to offer differentiated value-added services that meet customer expectations. Without the operations support of well-developed Business Support System/Operations Support System (BSS/OSS), it is difficult to timely and effectively provide competitive services upon customer request. In this paper, a suite of NGOSS-based Telecom OSS (TOSS) is developed for the support of fulfillment and assurance operations of telecom services and IT services. Four OSS groups, TOSS-P (intelligent service provisioning), TOSS-N (integrated large-scale network management), TOSS-T (trouble handling and resolution), and TOSS-Q (end-to-end service quality management), are organized and integrated following the standard telecom operation processes (i.e., eTOM). We use IPTV and IP-VPN operation scenarios to show how these OSS groups co-work to support daily business operations with the benefits of cost reduction and revenue acceleration.

• 융합정보논문지
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• 제9권12호
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• pp.39-46
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• 2019

엔터프라이즈 환경의 표준화 경쟁은 백엔드의 데이터 티어로 시작하여 대표적인 엔터프라이즈 미들 티어가 스프링 프레임워크로 받아들여짐으로써 표준화로 안정화되고 있는 실정이다. 또한 점차 빠른 주기로 새로운 디바이스의 출현으로 웹과 모바일 서비스에 대한 호환성 확보가 웹 서비스 기업들의 중요한 경쟁력이 되고 있다. 그러나 국내 기업들은 이러한 정보화 시대의 격변한 환경 변화에 적절한 역량있는 기술 인력을 확보하지 못하고 있으며, 교육중심 대학들의 교육과정에서도 새로운 역량중심의 교육과정의 요구를 반영하지 못하고 있는 실정이다. 따라서 본 연구에서는 이러한 엔터프라이즈 시스템 플랫폼 환경에서 필요한 역량중심의 기술을 습득과 교육과정을 개발하기 위하여 스프링 프레임워크 환경에서 스프링 데이터 JPA를 활용한 시스템을 분석 및 설계 단계별로 문서화 작성을 통하여 구현하였다. 향후 엔터프라이즈 환경에서의 바로 적용할 수 있는 풀 스택 역량중심의 교육과정 및 캡스톤 디자인 교육과정의 참조 모델을 제공하고자 한다.

• Tribology and Lubricants
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• 제37권2호
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• pp.48-53
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• 2021

Wind energy is considered as the most competitive energy source in terms of power generation cost and efficiency. The power train of the pitch drive for a wind turbine uses a 3-stage complex planetary gear system in being developed locally. A gear train of the pitch drive consists of an electric or hydraulic motor and a planetary decelerator, which optimizes the pitch angle of the blade for wind generators in response to the change in wind speed. However, it is prone to many problems, such as excessive repair costs in case of failure. Complex planetary gears are very important parts of a pitch drive system because of strength problem. When gears are designed for the power train of a pitch drive, it is necessary to analyze the fatigue strength of gears. While calculating the specifications of the complex planetary gears along with the bending and compressive stresses of the gears, it is necessary to analyze the fatigue strength of gears to obtain an optimal design of the complex planetary gears in terms of cost and reliability. In this study, the specifications of planetary gears are calculated using a self-developed gear design program. The actual gear bending and compressive stresses of the planetary gear system were analyzed using the Lewes and Hertz equation. Additionally, the calculated specifications of the complex planetary gears were verified by evaluating the results from the Stress - No. of cycles curves of gears.

• Journal of Microbiology and Biotechnology
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• 제31권4호
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• pp.559-569
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• 2021

As one of the major types of lung cancer, non-small cell lung cancer (NSCLC) accounts for the majority of cancer-related deaths worldwide. Treatments for NSCLC includes surgery, chemotherapy, and targeted therapy. Among the targeted therapies, resistance to inhibitors of the epidermal growth factor receptor (EGFR) is common and remains a problem to be solved. MET (hepatocyte growth factor receptor) amplification is one of the major causes of EGFR-tyrosine kinase inhibitor (TKI) resistance. Therefore, there exists a need to find new and more efficacious therapies. Deoxypodophyllotoxin (DPT) extracted from Anthriscus sylvestris roots exhibits various pharmacological activities including anti-inflammation and anti-cancer effects. In this study we sought to determine the anti-cancer effects of DPT on HCC827GR cells, which are resistant to gefitinib (EGFR-TKI) due to regulation of EGFR and MET and their related signaling pathways. To identify the direct binding of DPT to EGFR and MET, we performed pull-down, ATP-binding, and kinase assays. DPT exhibited competitive binding with ATP against the network kinases EGFR and MET and reduced their activities. Also, DPT suppressed the expression of p-EGFR and p-MET as well as their downstreat proteins p-ErbB3, p-AKT, and p-ERK. The treatment of HCC827GR cells with DPT induced high ROS generation that led to endoplasmic-reticulum stress. Accordingly, loss of mitochondrial membrane potential and apoptosis by multi-caspase activation were observed. In conclusion, these results demonstrate the apoptotic effects of DPT on HCC827GR cells and signify the potential of DPT to serve as an adjuvant anti-cancer drug by simultaneously inhibiting EGFR and MET.

• 전자통신동향분석
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• 제34권1호
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• pp.75-85
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• 2019

Quantum technology is undergoing a revolution. Theoretically, strange phenomena of quantum mechanics, such as superposition and entanglement, can enable high-performance computing, unconditionally secure communication, and high-precision sensing. Such theoretical possibilities have been examined in the last few decades. The goal now is to apply these quantum advantages to daily life. Europe, where quantum mechanics was born a 100 years ago, is struggling to be placed at the front of this quantum revolution. Thus, the European Commission has decided to invest 1 billion EUR over 10 years and has initiated the ramp-up phase with 20 projects in the fields of communication, simulation, sensing and metrology, computing, and fundamental science. This program, approved by the European Commission, is called the "Quantum Technology Flagship" program. Its first objective is to consolidate and expand European scientific leadership and excellence in quantum research. Its second objective is to kick-start a competitive European industry in quantum technology and develop future global industrial leaders. Its final objective is to make Europe a dynamic and attractive region for innovative and collaborative research and business in quantum technology. This program also trains next-generation quantum engineers to achieve a world-leading position in quantum technology. However, the most important principle of this program is to realize quantum technology and introduce it to the market. To this end, the program emphasizes that academic institutes and industries in Europe have to collaborate to research and develop quantum technology. They believe that without commercialization, no technology can be developed to its full potential. In this study, we review the strategy of the Quantum Europe Flagship program and the 20 projects of the ramp-up phase.