능동적 트라이 압축을 이용한 고속 IP 검색

오승현,Oh, Seung-Hyun 한국정보처리학회 2003 정보처리학회논문지 A Vol.10 No.5

리우터의 IP 주소검색은 라우터에 도착한 IP 패킷의 목적지 주소를 이용하여 적절한 출력링크를 검색하고 결정하는 것이다. IP 주소검색은 라우터 성능의 병목지점 중의 하나로써 고속 백본망에 필요한 초고속 라우터 개발에 필수적인 부분이다. 본 논문은 보통의 펜티엄 CPU에서 능동적인 트라이(Trie) 압축기법을 이용하여 작은 메모리만으로 기가비트급 IP 주소검색을 실시할 수 있는 동적 트라이 압축(Dynamic Trie Compression) 자료구조를 소개한다. DTC 자료구조는 트라이를 압축하여 포워딩 테이블을 만들 때 테이블의 크기와 검색속도의 상관관계를 고려하여 능동적으로 테이블의 크기를 선태할 수 있다. 또한 트라이를 압축할 때 트라이의 구조를 반영하여 자료구조의 크기를 최소화함으로써 포워딩 테이블에 대한 IP 주소검색이 고속의 SRAM 캐시 검색이 되도록 한다. 실험결과에서 DTC 자료구조는 다양한 라우팅 테이블에 대해 능동적으로 최적의 압축을 제공함으로써 보통의 펜티엄 CPU에서 최대 $12.5{\times}10^5$ LPS(Lookup per second)를 기록하였다. IP address lookup of router searches and decide proper output link using destination address of IP packet that arrie into router. The IP address lookup is essential part in te development of high-speed router needed to high-speed backbone network as one of bottleneck of router performance. This paper introduces DTC data structure that can support gigabit IP address lookup by dynamic trie compression technique that just uses small memory in conventional Pentium CPU. When make a forwarding table by trie compression, the DTC can dynamically select a size of data structure with considering correlation between table's size and searching speed. Also, when compress the prefix trie, DTC makes IP address lookup on the forwarding table of a search on the high speed SRAM cache by minimizing the size of data structure reflecting the structure of the trie. In the experiment result, the DTC data structure recorded performance of maximum $12.5{\times}10^5$ LPS (lookup per second) in conventional Pentium CPU through a dynamic building of most suitable compression over variety of routing tables.

회원작품 - 홍천 노일리 단독주택

오승현,Oh, Seunghyun 대한건축사협회 2020 建築士 Vol.613 No.-

제2형 당뇨병 환자에서 혈당강하제와 보중익기탕 병용 투여가 혈당 변화에 미치는 영향 및 안전성 연구

오승현,정우녕,송미령,노지원,안영민,안세영,이병철,Seung-hyun Oh,Woo-nyoung Jung,Mee-ryoung Song,Ji-won Noh,Young-min Ahn,Se-young Ahn,Byung-cheol Lee 대한한방내과학회 2023 大韓韓方內科學會誌 Vol.44 No.3

Objective: This study aimed to assess the safety and effect on glucose level of Bojungikgi-tang in patients with type 2 diabetes mellitus. Methods: To review patients' clinical characteristics and laboratory tests retrospectively, we investigated 15 hospitalized patients with type 2 diabetes mellitus who took Bojungikgi-tang at Kyung Hee University Korean Medical Hospital for at least one day between January 2012 and December 2022. The blood glucose levels, including fasting blood sugar (FBS), 2-hour postprandial glucose (PP2) levels, and glycated hemoglobin level, were collected to determine the effect of the Bojungikgi-tang on blood sugar changes. Furthermore, to evaluate the safety of Bojungikgi-tang, hepatic function and renal function tests were implemented, including aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, γ-glutamyltransferase, blood urea nitrogen, creatinine, and Modification of Diet in Renal Disease estimated glomerular filtration rate. Results: When Bojungikgi-tang and a standard treatment for diabetes were administered for patients with type 2 diabetes, it was confirmed that there were no statistically significant changes in FBS and PP2 levels in the analysis of each medication taken. There was no significant difference in the safety profile after taking Bojungikgi-tang. Conclusions: The combined administration of Bojungikgi-tang with standard hypoglycemic medication for patients with type 2 diabetes may not affect blood glucose levels and safety.

몽고리안 저빌의 출생후 Harderian gland 분비세포 미세구조의 전자현미경적 고찰

오승현,윤영민,박지영,윤여성,이준섭,성제경,Oh, Seung-hyun,Yun, Young-min,Park, Ji-young,Yoon, Yeo-sung,Lee, Joon-sup,Seong, Je-kyung 대한수의학회 2000 大韓獸醫學會誌 Vol.40 No.2

Harderian glands are the unique organs in several mammals, which human and non-human primates do not have. We report the ultrastructural changes in the postnatal developmental periods of Harderian glands in Mongolian gerbil(Meriones unguiculatus). Male and female Mongolian gerbils were sacrificed on days 3, 10, 30 and 60 after birth and their Harderian glands were observed by transmission electron microscope. The obtained results were summarized as follows; 1. In 3-day-old Mongolian gerbils, Harderian gland was composed of one excretory duct and immature tubules which have two type cells, dark and light cells, identified electron-dense and electron-lucent respectively. 2. In 10-day-old Mongolian gerbils, small lipid vacuoles began to be found in the cytoplasm of the secretory cells of the Harderian gland. Mitochondria, Golgi apparatus, polysomes and slash were more abundant in the cytoplasm of dark cells than those of light cells. The arrangement of tubules in the gland was much more condensed than that of 3-day-old Mongolian gerbils. 3. In 30-day-old Mongolian gerbils, the secretory cells of the tubule were typically columnar in shape and there was one type cell in the tubule. Most of the columnar secretory cells contained various size vacuoles. 4. In 60-day-old Mongolian gerbils, the Harderian gland possessed the typical structural characteristics of adults. The mature glandular structures were more significant than those of 30-day-old animals.

몽고리안 저빌의 Harderian gland의 출생후 형태학적 변화

오승현,박지영,윤여성,김대중,남상윤,이준섭,성제경,Oh, Seung-hyun,Park, Ji-young,Yoon, Yeo-sung,Kim, Dae-joong,Nam, Sang-yoon,Lee, Joon-sup,Seong, Je-kyung 대한수의학회 1999 大韓獸醫學會誌 Vol.39 No.1

This investigation was carried out to study morphological and chronological aspects of the development of the Harderian gland in the Mongolian gerbil(Meriones unguiculatus). Male and female Mongolian gerbils were sacrificed on days 1, 3, 5, 10, 30 and 60 after birth and their Harderian glands were processed for light microscopic observation. The results obtained were summarized as follows; 1. In 1-day-old Mongolian gerbil, Harderian gland was well distinguished from other tissue structures. It was composed of several immature tubules, and these tubules were separated each other by undifferentiated mesenchymal connective tissues. 2. In 3-day and 5-day-old Mongolian gerbils, the arrangement of tubules in the gland was more condensed than that of 1-day-old Mongolian gerbil. The excretory ducts started to appear in the connective tissues located between lobes. 3. In 10-day-old Mongolian gerbil, small lipid vacuoles began to be found in the cytoplasm of the secretory cells of the Harderian gland. There were some mucus-secreting cells within the epithelium of the excretory duct found in the interlobar connective tissues. 4. In 30-day-old Mongolian gerbil, there was markedly increased number of the tubules in the glands. The epithelial cells of the tubules were typically columnar in shape. Most of the columnar epithelial cells contained many small lipid vacuoles, although a few cells contained large lipid vacuoles. 5. In 60-day-old Mongolian gerbil, the Harderian gland exhibited the typical structural characteristics of the adult gland. The mature glandular structures were more distinct than those of 30-day-old animals.

회원작품 - 구기동 삼대(三代)가 사는 집

오승현,Oh, Seunghyun 대한건축사협회 2019 建築士 Vol.602 No.-

한국 야생 등줄쥐의 고해상도 염색체분염상

오승현,윤여성,진희경,성제경,Oh, Seung-hyun,Yoon, Yeo-sung,Jin, Hee-Kyung,Seong, Je-kyung 대한수의학회 2004 大韓獸醫學會誌 Vol.44 No.2

We investigated the cytogenetic characteristics of male black-striped field mouse (Apodemus agrarium) in Korea. Chromosome slides were obtained from blood cell cultures which were synchronized with thymidine blocking or not. In the chromosome slide which synchronization with thymidine blocking was employed on, the GTG(G bands by trypsin using Giemsa)-bands of high resolution were observed. The male black-striped field mouse has 48 chromosomes composed 46 autosomes and XY sex chromosomes. The centromeric regions of autosomes were positive to GTG-banding. According to this investigation, thymidine blocking in cell culture process was useful to get lengthened chromosomes. It may be necessary to employ RBG-banding technique to investigate complementary band patterns between R- and G-banding in black-striped field mouse.

한국재래산양의 핵형분석

오승현,윤영민,윤여성,이준섭,이흥식,성제경,Oh, Seung-hyun,Yun, Young-min,Yoon, Yeo-sung,Lee, Joon-sup,Lee, Heungshik S.,Seong, Je-Kyung 대한수의학회 1999 大韓獸醫學會誌 Vol.39 No.5

We investigated the cytogenetic characteristics of Korean native goat(Capra hircus). Chromosome slides were prepared from peripheral blood cell cultures. GTG, GBG, RBG and CBG-banding techniques were employed on those slides. The high resolution karyotype of Korean native goat could be made with the incorporation of BrdU. Korean native goat has 60 chromosomes composed of 58 autosomes and XY or XX sex chromosomes. All of autosomes of Korean native goat were acrocentric chromosomes. X chromosome was submetacentric and Y chromosome was metacentric. The GTG, GBG and RBG-band patterns of Korean native goat were similar to those of other goats. CBG-band regions were distinct at the proximal portion of the long arms of all autosomes in Korean native goats. According to our investigation, there was no significant difference in chromosomal band patterns between Korean native goat and other goats. It might be necessary to use molecular genetic markers for clarifying the genetical characteristics of Korean native goat whose biological characteristics are not clearly defined.

양질의 보철 제작을 위한 치과의사와 치과기공사 간의 의사소통의 중요성

오승현,Oh, Seung-hyun 대한심미치과학회 2017 Journal of the Korean Academy of Esthetic Dentistr Vol.26 No.2

일반적인 보철치료 과정에서 치과의사와 치과기공사 간의 의사소통 부족으로 인한 재치료 사례가 빈번하게 일어나고 있다. 대규모 치료의 성공은 작은 치료에서 부터 시작한다. 이 보고서에서는 그것과 관련한 간단한 사례를 통해 커뮤니케이션의 중요성을 되새긴다. 좀 더 나은 색과 형태를 재현하기 위해서 치과의사는 치과기공사에게 구체적이고 정확한 정보와 의견을 전달해야 하고 치과기공사는 이것을 올바로 분석하고 제대로 표현할 수 있는 기술을 보유해야 한다. 이 과정에서 반드시 서로가 의견교환을 통해 좀더 나은 보철을 제작할 수 있는 환경을 구축해야 한다. There are frequent cases of retreatment due to lack of communication between dentists and dental technicians during general prosthetic treatment. The success of large-scale therapy begins with small treatments. This report reminds you of the importance of communication through a simple example. To reproduce better colors and shapes, the dentist must provide specific and accurate information and feedback to the dental technician, and the dental technician must have the skills to accurately analyze and express it. In this process, we need to create an environment where we can exchange mutual opinion and produce better prostheses.

비트 - 맵 트라이를 이용한 빠른 라우팅 검색

오승현(Seung-Hyun Oh),나승구(Seung-Gu Na),안종석(Jong-Suk Ahn) 한국정보과학회 2000 한국정보과학회 학술발표논문집 Vol.27 No.1A

기가비트 속도를 지원하는 고속 라우터의 IP 주소 검색은 소프트웨어로 구현할 수 없다는 일부의 믿음과는 달리 소프트웨어만으로도 고속 IP 주소 검색의 구현이 가능하다. 기가비트라우터의 IP 주소 검색은 최장프리픽스일치 기법을 사용하여 라우팅 엔트리를 검색하는데, 5Gbps 속도를 지원하기 위해서는 512byte의 패킷을 800 nsec 이하의 속도로 처리하여야 한다. 본 논문에서는 범용 펜티엄 프로세서의 캐쉬 크기에 적합한 고속 라우팅을 위한 포워딩 테이블 구조를 제안하였으며, 400㎒의 펜티엄 Ⅱ 프로세서를 이용한 실험에서 초당 수백만개의 IP 주소 검색을 실현하였다. 제안된 포워딩 테이블은 약 48,000여개의 실제 라우팅 엔트리에 대해 284Kbyte의 매우 작은 크기로 작성되었는데, 이 크기는 펜티엄 프로세서의 L2 케쉬에 저장될 수 있는 작은 크기이다. 제안된 포워딩 테이블을 이용한 평균 검색 시간은 라우팅 테이블 별로 320~530 nsec가 소요되었다.