• Electronics and Telecommunications Trends
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• v.35 no.5
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• pp.139-150
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• 2020

Fifth-generation (5G) wireless communication supports low latency of up to 1 ms or less, 20 Gbps of data rate, and more than 1 million connections. With these technical advantages, machines and equipment can be precisely adjusted, allowing 5G to be applied to industrial applications. To expand the industrial application of 5G wireless communications, major countries have introduced dedicated 5G, allowing specific companies to build and use 5G directly. Germany, UK, and Japan allocate 100 MHz, 416 MHz, and 1,200 MHz, respectively, of bandwidth dedicated to 5G. Companies with local licenses from the government are expected to accelerate the application of 5G at a low cost and low-frequency range. Therefore, Korea should introduce private 5G to foster 5G-related industrial ecosystems and successfully implement the fourth industrial revolution.

• Electronics and Telecommunications Trends
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• v.29 no.5
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• pp.136-144
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• 2014

오늘날 ICT(Information & Communication Technology)분야의 최대 화두를 꼽는다면 빅데이터, IoT(Internet of Things), 그리고 클라우드를 빼놓을 수 없다. 아직 국내에서는 클라우드 관련 산업 및 시장이 본격적으로 활성화되고 있지는 못하지만, 다양한 규모와 형태의 클라우드 인프라를 손쉽게 구축하고 관리할 수 있는 클라우드 운영체제의 출현과 기술 고도화로 기업의 ICT 환경을 클라우드로 전환하는 사설 클라우드의 구축이나 공용 클라우드와 사설 클라우드를 적절히 함께 운용하는 하이브리드 클라우드에 대한 관심이 매우 높은 실정이다. 현재 이러한 흐름을 이끌며 가장 많은 주목을 받고 있는 것이 바로 공개 소프트웨어 기반의 클라우드 운영체제인 OpenStack이다. 본고에서는 OpenStack의 최근 배포판인 Icehouse를 중심으로 OpenStack의 구성과 주요 특징 그리고 기술동향을 정리한다.

• Sijohaknonchong
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• v.23
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• pp.161-188
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• 2005

The purpose of this study was to delve into the morphological types of Sijo in an effort to determine the morphological structure of Sasul-sijo, and it's also attempted to present standard about how to discriminate Pyong-si, Eos-sijo and Sasul-sijo from one another from a morphological standpoint. It's suggested that Si with tee Jangs, six verses and 12 stanzas or more, with three Jangs, seven verses and 14 stanzas or more, and with three Jangs, eight verses and 16 stanzas or more should respectively be called Pyong-sijo, Eos-sijo and Sasul-sijo. After what Sijo was and what's not were discussed, how to distinguish Eos-sijo from Sasul-sijo was described, and finally, the structure of Sasul-sijo was presented. As for Sijo and non-Sijo, the types of works that consisted of tee Jangs, like Sijo, yet didn't suit its framework and Yuljo and were written in Chinese characters were regarded as non-Sijo. Concerning discrimination between Eos-si and Sasul-sijo, the type of Sijo that included one more or higher number of verse(s) and two more or higher number of stanzas in one of three Jangs was defined as Eos-sijo, and the type of Sijo that involved two more or higher number of verses and four more or higher number of stanzas in one of three Jangs was called Sasul-sijo. In other words, Eos-sijo contained one more verse in one of tee Jangs, and Sasul-sijo included one more Jang in one tee Jangs. The sort of Sijo that contained one more Jang in one of three Jangs could be viewed as Sasul-sijo. Regarding the structure of Sasul-si, there should be three Jangs, eight verses and 16 stanzas in one piece of Sasul-sijo. Any type of Sijo that contained two more or higher number of verses and four more or higher number of stanzas could be called Sasul-sijo. Such an addition of verse and stanza could done in various ways. The examples were (1) adding stanzas the first Jang, 2) adding stanzas to the second Jang, (3) adding stanzas to the final Jang, (4) adding stanzas to both the first and Second Jangs, (5) adding stanzas to th the second and final Jangs, and (6) adding stanzas to all the first, second and third Jangs at the same time. Besides, there was an extremely broad gap between the numbers of verse and stanza in Sasul-sijo, which ranged from a low of eight stanzas to a high of 87 ones in one of three Jangs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5294-5302
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• 2014

The development of public-key-based technique that enables a variety of services(E-government, e-banking, e-payment, etc.) evaluated as having complete safety. On the other hand, vulnerabilities(e.g, heartbleed bug, etc.) are constantly being discovered. In this paper, a public key infrastructure to verify the safety and reliability, the collision rate using OpenSSL key pair was analyzed. the experiment was performed using the following procedure. Openssl was used to create five private certification agencies, and each of the private certificate authority certificates to create 2 million, generating a total of 10 million by the certificate of the key pair conflicts analysis. The results revealed 35,000 in 1 million, 0.35% chance of a public key, a private key conflict occurred. This is sufficient in various fields(E-payment, Security Server, etc.). A future public-key-based technique to remove the threat of a random number generator, large minority issues, in-depth study of selection will be needed.

• Electronics and Telecommunications Trends
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• v.28 no.5
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• pp.122-132
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• 2013

오늘날 클라우드 서비스가 확산되면서 공용 클라우드 뿐만 아니라 사설 클라우드나 하이브리드 클라우드에 대한 관심도 높아지고 있다. 특히 다양한 규모와 형태의 클라우드 인프라를 손쉽게 구축하고 관리할 수 있는 클라우드 운영체제에 대한 관심은 최근 급증하고 있는 추세이다. 또한 정보통신 인프라에서 네트워크가 차지하는 비중만큼이나, 클라우드 서비스에서 멀티테넌시 네트워크 구성, 다양한 네트워크 하부 기술의 수용, 가상 네트워크 인프라의 동적 프로비저닝 등을 포함하는 클라우드 네트워크 기술에 대한 관심과 기술개발 노력이 더욱 집중되고 있다. 본고에서는 현재 가장 주목받고 있는 공개 소프트웨어 기반의 클라우드 운영체제인 OpenStack의 구조와 클라우드 네트워크 기술에 대한 주요 특징을 정리한다.

• Electronics and Telecommunications Trends
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• v.25 no.2
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• pp.57-67
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• 2010

최근에 3.5G, 4G 이동통신, WiMax 등 다양한 고속 무선 데이터 서비스의 발달이 급속도로 진행됨에 따라 기지국을 위한 무선 백홀의 전송속도가 현재 보다 급격히 높아질것으로 예상되며, 광 백본망에 연결되지 않은 빌딩들을 위한 광통신망과 빌딩간 'Last Mile' 구간에 대한 경제적인 통신망 확보가 요구되고 있다. 본 고에서는 경제적으로 Gbps급 광 백본망과 가입자를 연결하거나, Gbps급 사설통신망 및 백홀에 이용할 수 있는 E-band 이용 Multi-Gbps급 고정 점대점 통신 시스템과 송수신기 핵심 구성 부품의 기술 개발 동향을 소개하고자 한다.

• Electronics and Telecommunications Trends
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• v.14 no.5 s.59
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• pp.1-15
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• 1999

본 고에서는 B-ISDN 망의 NNI 프로토콜로 B-ISUP과 PNNI가 동시에 수용되는 공중 망에서 ITU-T E.164 주소체계 사용에 따른 장.단점을 살펴보고, 공중망 교환기에 ATM Forum 신호 권고안을 수용하면서 지금까지 주로 사설 ATM 망에서 사용되어 온 AESA DCC, ICD/IOTA 주소체계를 공중망에 수용하기 위한 검토사항, 필요성, 수용방법을 기술하고, 국내에서 구축중인 B-ISDN 망의 AESA DCC, ICD 주소형태(address format) 및 각 주소계위(address hierarchy)의 의미, 이를 지원하기 위한 공중망 교환기의 기능에 대하여 기술하고자 한다.

• Electronics and Telecommunications Trends
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• v.14 no.5 s.59
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• pp.55-69
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• 1999

초고속통신망에서 서비스 사업자 시스템에 적용될 번호체계, 상호접속 기준에 대한 기본적 요건과 기술적 표준 규정 등에 관한 연구가 미비한 실정이다. 초고속 서비스 사업자 망과 초고속 통신망에 접속 및 운용되는 시스템에서 초고속망의 번호계획을 위하여 연동을 고려할 대상 망은 기존의 전화망, 데이터망, ATM 망 및 ISDN 등이 있다. 본 고에서는 인터넷망과 ATM 망과의 연동시 발생할 번호체계의 상호접속 및 연동방안에 대하여 논한다. 현재 제정된 ITU-T 표준 규격을 중심으로 현존하는 망과 초고속 번호체계간의 상호 연동방안을 기술하였다. 또한 ATM 포럼 등의 사설기관에서 사용하고 있는 번호체계도 추가적으로 검토하였다.

• Journal of Ginseng Research
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• v.30 no.3
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• pp.128-131
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• 2006

Saponin isolated from red ginseng was added to cultures of Staphylococcus aureus and Candida albicans in order to investigate saponin's influence on the growth of some pathogenic bacteria and yeasts. S. aureus and C. albicans were incubated at $38^{\circ}C\;and\;28^{\circ}C$ for 5 days with 100 rpm after addition of 0.013, 0.125, 0.500 and 1.000% (w/v, final concentration) of saponin, respectively. After incubated for 1 day, 2 days or 5 days, pH and viable cell counts of the cultures were investigated. The both of pH of S. aureus and C. albicans were decreased in concentration-dependent manner. Viable cell counts after incubation of 5 days were $1.0\;{\times}\;10^8,\;9.4\;{\times}\;10^7,\;1.0\;{\times}\;10^3$ and 0 CFU/ml, respectively, when compared with $1.8{\times}10^8\;CFU/ml$ of saponin non-treated group. Especially, 1.0% concentration of saponin inhibited completely the growth of S. aureus. While, viable cell count in C. albicans somewhat lower values than that of saponin non-treated group, but the values not significant. These results suggest that ginseng saponin inhibit the growth of S. aureus in a concentration-dependent manner, but not the growth of C. albicans.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.3
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• pp.230-238
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• 2003

An effect on the enhancing production of hollow 'jumbo' structures and the condition of artificial reefs (dice and hollow jumbo structure) by side scan sonar were described. The experiment of the capture of fish in the jumbo structures and control site (non-artificial site) by trammel net and traps was done twice every year from 1998 to 2000. The relative catches by trammel net between in the jumbo structure and in the control site was significantly different in number and in weight at 5% level and also that by traps significantly different in weight. The t-test of the catch of finespotted flounder showed that the hollow jumbo structure was regarded as a breeding field because the average size of the flounder in the jumbo site was smaller than that in the control site. The search on the condition of the artificial reefs (dice and hollow jumbo structure) was performed by side scanning sonar which showed various phase of it such as accumulated, dispersed, scouring and partly buried. The result implied that in the area of sand bottom with strong tide like the western sea of Korea, the current criterion for constructing artificial reef should be modified because of the sand moving on the bottom.