• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.181-187
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• 2005

This paper proposes and implements a service model to transfer messages safely for PDA on CDMA wireless network and a secure massage transfer protocol which considers characteristics of PDA. Proposed service uses SMS(Short Message Service) connect to a off-line client device with the wired network for data communication. After receiving SMS message, client device processes the SMS message and creates a data channel through RAS(Remote Access Service), then the data of the server can be pushed to clients. The implemented security protocol can provide safe data transmission on each communication line through two way channels(SMS and data). Also, by using security nonce table, this protocol can reduce a number of transmissions for exchanging a safe session key, so intensity of encryption can be increased.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.20-23
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• 2013

Recently for the transfer of large size video file between sites for high-definition craft editing used by broadcasting company the Public Network is used a lot. In the IP Public Network with QoS(Quality-of-Service) not guaranteed, degradation of performance has several causes. In this paper, we have analyzed the causes of low performance to transfer a large size HD video file in long distance, in order to maximize the effectiveness, the high efficiency network could be implemented enabling the highspeed of HD video file using the connection with networks between hosts through packet creation and multi-session of Parallel TCP. We survey the result of high speed transfer system and verify the efficient transfer method using Public IP Network for large HD video file transfer in broadcasting cooperation.

• Journal of Embryo Transfer
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• v.30 no.3
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• pp.149-159
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• 2015

This study was designed to know the possibility in repeat uses of elite donor cows for getting mass production of OPU-derived embryo production (OPU-IVP). Ultrasound transvaginal ovum pick-up (OPU) performed in 6 Korean native cows was aged 4 to 10 years old. The aspiration of immature oocytes for OPU derived embryo was carried out 2 times per week, and OPU-IVP of $1^{st}$ period was carried out 22~48 sessions from each donors. And the break time for OPU-IVP of $2^{nd}$ period after $1^{st}$ OPU from each donors were 2~25 months. The OPU-IVP of $2^{nd}$ period each donors conducted total 15~65 times for 2~8 months by an ultrasonographic, was guided follicular aspiration system. The average numbers of collected oocytes, grade 1 + grade 2(G1+G2) oocytes and cleavage embryo from $1^{st}$ period OPU-IVP were significantly differences between donors (p<0.05). Total collected oocytes of donor D were significantly higher compared with donors of A, B, C, E and F (average 17.0 per session vs. 11.2, 10.1, 8.5, 10.2 and 9.6; p<0.05) and also oocytes of G1+G2 were significantly higher compared with r A and D and subsequently to donors of B, C, E and F (average 7.9 and 8.5 per session vs. 5.0, 2.7, 6.0 and 1.6; p<0.05). Cleavage rate of donor D was significantly higher compared with donors of A, B, C, E and F (average 13.1 per session vs. 10.1, 9.1, 6.9, 8.9 and 6.7; p<0.05). The average numbers of OPU-IVP for $1^{st}$ period was significantly higher from donors of B, D and E than those from donors of A, C and F (average 6.5, 7.1 and 6.5 per session vs. 3.5, 4.2 and 2.8; p<0.05). The possibility investigation of $2^{nd}$ OPU-IVP was carried out after 2~25 months rest periods from $1^{st}$ period OPU session. Total average numbers of collected oocytes, cleavages and blastocyst development rates were significantly higher from $1^{st}$ period OPU compared with $2^{nd}$ period one (p<0.05). The OPU-IVP efficiency by break for more embryo production from elite cow was analysis comparing without rest of donor A, under 6 months rest period as B and over 6 months rest period as C and then the average numbers of collected oocytes, cleavages and blastocysts were significantly higher from A group (11.8, 9.5 and 5.2 per session) than those from B and C groups (7.9, 6.2 and 2.6 vs. 9.2, 7.5 and 3.9, p<0.05), and also C group was significantly higher than B group. In conclusion, $1^{st}$ period OPU-IVP was more efficient compared with $2^{nd}$ period repeated uses of donor, and the break times for additional production of embryo on donor were needed more than over 6 months after $1^{st}$ period OPU-IVP. This repeating uses of elite donor cows given more emphasis for getting the opportunity on mass production of elite cow OPU-IVP embryo should be increased G1+G2 possibility of genetic improvement of livestock within short period.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.8
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• pp.918-929
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• 1999

동기식 스트림 암호통신 방식을 사용하는 암호통신에서는 암/복호화 과정 수행시 암호통신 과정에서 발생하는 사이클슬립으로 인해 키수열의 동기이탈 현상이 발생되고 이로 인해 오복호된 데이타를 얻게된다. 이러한 위험성을 감소하기 위한 방안으로 현재까지 암호문에 동기신호와 세션키를 주기적으로 삽입하여 동기를 이루는 주기적인 동기암호 통신방식을 사용하여 왔다. 본 논문에서는 CDMA(Cellular Division Multiple Access) 이동망에서 데이타서비스를 제공할 때 사용되는 점대점 프로토콜의 주소영역의 특성을 이용하여 단위 측정시간 동안 측정된 주소비트 정보와 플래그 패턴의 수신률을 이용하여 문턱 값보다 작은경우 동기신호와 세션키를 전송하는 비주기적인 동기방식을 사용하므로써 종래의 주기적인 동기방식으로 인한 전송효율성 저하와 주기적인 상이한 세션키 발생 및 다음 주기까지의 동기이탈 상태의 지속으로 인한 오류확산 등의 단점을 해결하였다. 제안된 알고리즘을 링크계층의 점대점 프로토콜(Point to Point Protocol)을 사용하는 CDMA 이동망에서 동기식 스트림 암호 통신방식에 적용시 동기이탈율 10-7의 환경에서 주기가 1sec인 주기적인 동기방식에서 요구되는 6.45x107비트에 비해 3.84x105비트가 소요됨으로써 전송율측면에서의 성능향상과 오복호율과 오복호 데이타 비트측면에서 성능향상을 얻었다. Abstract In the cipher system using the synchronous stream cipher system, encryption / decryption cause the synchronization loss (of key arrangement) by cycle slip, then it makes incorrect decrypted data. To lessen the risk, we have used a periodic synchronous cipher system which achieve synchronization at fixed timesteps by inserting synchronization signal and session key. In this paper, we solved the problem(fault) like the transfer efficiency drops by a periodic synchronous method, the periodic generations of different session key, and the incorrectness increases by continuing synchronization loss in next time step. They are achieved by the transfer of a non-periodic synchronous signal which carries synchronous signal and session key when it is less than the threshold value, analyzing the address field of point-to-point protocol, using the receiving rate of address bits information and flag patterns in the decision duration, in providing data services by CDMA mobile network. When the proposed algorithm is applied to the synchronous stream cipher system using point-to-point protocol, which is used data link level in CDMA mobile network, it has advanced the result in Rerror and Derror and in transmission rate, by the use of 3.84$\times$105bits, not 6.45$\times$107bits required in periodic synchronous method, having lsec time step, in slip rate 10-7.

• Korean Journal of Veterinary Service
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• v.44 no.4
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• pp.227-237
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• 2021

Artificial insemination of Korean native cattle (KNC) is the predominant method for breed improvement. However, industrialization of embryo production and transfer is necessary to utilize the genetic potential of KNC. The aim of this study was to examine associations between KNC donor cows and ovum pick-up (OPU) conditions, in-vivo oocyte recovery, and embryo development. Oocyte recovery and blastocyst development rates were higher at 50 and 60 mmHg OPU vacuum pressure than at 40 mmHg, which was, however, not significant. Regarding follicle growth, injection of 500 ㎍ GnRH 36 hours before OPU significantly increased the number of OPU oocytes from an average of 4.6 to 7.6 (P<0.05); no significant difference in embryo development rates was observed. Significant differences were observed in the numbers of OPU oocytes, embryo development rates, and transplantable blastocysts per individual among nine KNC donors (P<0.05). Furthermore, although there was no difference in OPU oocyte recovery intervals in approximately 2~8 weeks, the number of recovered oocytes significantly decreased at the 12-week interval (P<0.05); there was no difference in embryo development rates. The number of oocytes and embryonic development rates only tended to decrease until the seventh OPU session, but decreased significantly until the eighth session (P<0.05). The average pregnancy rate after transfer of OPU-derived in-vitro embryos into recipient cows was 41.8%. To improve the efficiency of OPU egg recovery and in-vitro embryo production, considering KNC donor characteristics, vacuum pressure of 60 mmHg, GnRH pretreatment to induce follicle growth, and effective OPU egg recovery up to seven times at intervals of 2~4 weeks appears to be most suitable. This study may facilitate the industrialization of KNC embryo production and transfer using high-quality cows.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.682-685
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• 2002

VoIP(Voice over IP) Technology is highlighted because of easy adopting the value added services related voice In this paper, we described the Internet telephony service based on SIP. Especially, we described the extension for re-INVITE function. Re-INVITE function is useful for cail transfer service or conference service.

• Journal of Korea Society of Digital Industry and Information Management
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• v.5 no.2
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• pp.39-49
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• 2009

In this paper, we classify web-based social network into two types: open and community, and model user behavior in social activities. After that, we also propose the combination of instant messaging and web system as the method of support asynchronous/synchronous social activities. Furthermore, we introduce ImCoWeb prototype system that supports both asynchronous social activities (ex. social bookmark, comment, rate, and data share) and synchronous ones (ex. real-time communication, file transfer, co-browsing, and co-work). Because it is built on the existing instant messaging, it reduces costs by reusing the facilities such as session management, user management, and security of instant messaging.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.60.2-60.2
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• 2016

We present recent results of very long baseline interferometry (VLBI) observations of gamma-ray bright active galactic nuclei (AGNs) using Korean VLBI Network (KVN) at 22, 43, 86, and 129~GHz bands, which are part of a KVN key science program; Interferometric Monitoring of Gamma-ray Bright AGNs (iMOGABA). We selected a total of 34 radio-loud AGNs of which 30 sources are gamma-ray bright AGNs, including 24 sources monitored by the Fermi Gamma-ray Space Telescope using the Large Area Telescope on board. The selected sources consist of 24 quasars, 7 BL Lacs, and 3 radio galaxies. In this talk, we summarize recent results of the iMOGABA, including results of single-epoch multi-frequency VLBI observations of the target sources, conducted during a 24-hr session on 2013 November 19 and 20. All observed sources were detected and imaged at all frequency bands with or without a frequency phase transfer technique which enabled to detect and image 12 faint sources at 129 GHz, except for 0218+357 which was detected for only one baseline at all frequency bands.

• Annual Conference of KIPS
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• 2002.11b
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• pp.1419-1422
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• 2002

SIP(Session Initiation Protocol)는 기존의 VoIP(Voice over IP)를 위한 시스템에서 뿐만 아니라 호설정의 처리와 제어가 필요한 여러 인터넷 응용분야에 적용이 가능한 확장성이 뛰어난 프로토콜이다. 또한 HTTP(Hyper Text Transfer Protocol)와 유사한 텍스트 기반의 응용계층의 프로토콜로서 호처리시 절차가 비교적 간결하다. 본 논문에서는 이러한 SIP의 장점을 이용하여 화상회의를 위한 시스템을 구현하였다. 이때. 인증 기능을 부여하여 화상회의시 세션 연결을 위한 호설정을 이루는 과정에서 상대방을 인증할 수 있도록 하였고 인증방법으로는 메시지 인증기능과 함께 리플레이 공격(replay attack)의 방지기능을 가진 SIP 다이제스트 인증(Digest Authentication) 방법을 사용하였다. 본 화상회의 시스템에 사용된 SIP 사양은 최근에 발표된 RFC 3261을 기준으로 하였다.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.25-29
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• 2008

The CORBA that supports FPGA has not been used generally and it is difficult to implement and to develop the CORBA for FPGA. In this paper we propose the way to design FPGA to support a CORBA component. For FPGA to support the CORBA component, embedded processor provided by FPGA and PCI based CORBA is utilized. The PCI based CORBA is for improving data transfer throughput. This paper will be organized as follows. In Chapter I, existing research trend and background are presented for why we propose design of FPGA that support the CORBA component. In Chapter II, FPGA design for supporting CORBA components is proposed and described in detail. In Chapter III, simple experiment is tested to confirm the proposed FPGA design. Finally session 4 is conclusion of this paper.