• 디지털산업정보학회논문지
• /
• 제6권4호
• /
• pp.95-105
• /
• 2010

DNS(Domain Name System) is a huge distributed database that converts host name to IP address. We are expecting the importance of DNS is more increased because many Internet application services appear according to the continuous increase of Internet users and nearly all the Internet application services use DNS. To prevent the interruption of DNS service, DNS server is configured with primary DNS server and a secondary DNS server which takes the place of primary DNS server in case of the service interruption. But this scheme is difficult for providing DNS service constantly in case of DDoS attack, which brings about much network load or network problems in DNS server group. Therefore, This paper proposed the scheme to locally distribute load of DNS server, and the use of address system to group the distributed DNS servers. Also, it proposed the authentication scheme of the correspondent server in case the server is changed in DNS server group having grouping address. In this paper, it is shown that the prosed scheme guarantees the improved service reliability with maintaining the present service performance through the evaluation. Through this, we can expect the high improved DNS service can be provided in the Internet environment in the future.

• 한국의류학회지
• /
• 제23권5호
• /
• pp.623-634
• /
• 1999

The purpose of this study is to explore the culture of clothing of subgroups among adolescents by residence. In this research informants were selected by selective sampling and ethnographic methods such as field work depth interviews and open-ended descriptions were employed to interpret their culture of clothing. The results were followed. First our adolescents enjoyed the popular song as leisure and these popular culture was their inspiration source of style. Second adolescents were grouping the Kang-Bouk and the adolescents group preferred the style of popular singers and the Kang-Nam adolescents group preferred the musical competence of singers and specific type particularly Hip-Hop style. And in acception pattern of fashion style the Kang-Bouk groups accepted the recent fashion style continuously and wanted to be striking while the Kang-Nam groups accepted the various Hip-Hop styles and sought to comfort and suitability of that style. Third to consider the connotations of marketing the Kan-Bouk groups shopped on the street perceived as fashionable among peer groups and sought to the lower price but the Kang-Nam groups used the shops selling their original ip-Hop style without regard to the price and sites. Although there existed a two years' difference between the first and the second research(1996-1998) subgroups among adolescents according to the residence have had their own culture of clothing constantly. And a segmentation tendency by clothing behavior within the same adolescent generation is revealed more visibly.

• Journal of Animal Science and Technology
• /
• 제49권5호
• /
• pp.559-568
• /
• 2007

최근 들어 유전자 또는 DNA 분절의 반복수 변이 (CNV)에 관한 연구가 다수 수행되었으며, 그 분석 방법 및 기기 또한 다양하게 발달되었다. 본 연구는 Landrace 품종의 KIT 유전자 CNV 탐지를 위하여 다른 분석 방법들에 비하여 정확도가 높은 정량적 OLA 기법(qOLA)을 이용하였다. qOLA와 pyrosequencing assay의 조합하여 분석한 결과를 Landrace 44두에 대한 좌표 분석을 한 결과 I1/I1 또는 I3/i(IBe), I1/I2 또는 I3/IP, I1/I3, I1/IP 또는 I2/i(IBe), I2/I2, I2/IP의 6 genotype으로 분류되었으며, PROC FASTCLUS procedure을 이용한 통계 분석과 좌표 분석을 상호 비교한 결과 genotype의 분류가 100% 일치하였다. 기기간의 차이점을 조사하기 위해 qOLA_3100과 qOLA _3130의 관측치 비교를 실시한 결과 동일한 genotype 분류결과를 얻었다. 또한 정밀성 및 정확도 비교에서 qOLA_3100의 경우 표준편차와 변이계수의 평균이 2.33과 4.10로 qOLA_3130(2.67과 4.81)에 비하여 낮게 나타났다. qOLA 반응전 PCR 산물에 대하여 proteinase K 처리효과를 분석한 결과 pro- teinase K를 처리한 경우 전기영동 분석시 noise peak들이 제거되었으며 각 genotype의 이론적 비율에 보다 정확히 일치하였다.

• 한국통신학회논문지
• /
• 제37권6B호
• /
• pp.433-442
• /
• 2012

We have proposed a solution to multicast services and an advanced quality of service (QoS) mechanism on a packet transport system (PTS) based on PBB-TE. The point-to-multipoint (PtMP) connection in the PBB-TE system have been realized by grouping point-to-point (PtP) PTL trunks and mapping a BSI onto the PtP PTL trunks using a multicast backbone destination address. To provide end-to-end QoS of the PtMP services, the hierarchical QoS scheme for backbone service instances and connection-oriented paths has been implemented in the PTS. For providing different capabilities for service selection and priority selection, the PTS offers to customers three basic types of the port-based, C-tagged, and S-tagged service interface defined by the IEEE 802.1ah. To offer to customers different capabilities of the layer 3 applications and services, moreover, an IP-flow service interface have been added. In order to evaluate traffic performance for PtMP services in the PTS, the PtMP throughputs for the link capacity of 1 Gbps at the four service interfaces were measured in the leaves of the ingress edge node, the transit node, and the egress edge node. The throughputs were about 96 % because the B-MAC overhead of 22 bytes occupies 4% of the 512-byte packet. The QoS performance is ability to guarantee an application or a user a required bandwidth, and could be evaluated by the accuracy of policing or shaping. The accuracy of the policing scheme and the accuracy of the shaping scheme were 99% and 99.3% respectively.