LAN 에뮬레이션과 ATM API 응용의 성능 비교 분석

박문호,이봉환 大田大學校 産業技術硏究所 1998 산업기술연구소 論文集 Vol.9 No.1

LAN Emulation is a popular scheme to accomodate legacy LAN applications in ATM LAN Environments. LAN Emulation, however, can not provide full ATM services because of legacy transport and network protocols it adopts. To address this limitations, ATM Forum has defined "Native ATM Services : Semantic Description". In this paper, we developed an ATM API-based application and compared the performance of Native ATM services to that of LAN Emulation under ATM25 environments. Native ATM API-based application performed much better than LAN Emulation in two aspects such as average transmission delay and maximum bandwidth.

단기배양을 통한 말초혈액 CD34 양성세포의 체외증폭

박상준,김철희,배광봉,김현수,김종숙,윤환중,조덕연,김삼용 충남대학교 의과대학 지역사회의학연구소 1997 충남의대잡지 Vol.24 No.1

Background: It is suggested that clinical practice in the areas of bone marrow transplantation and gene therapy might rely on the ex vivo expansion of hematopoietic stem/progenitor cells. However, the condition for ex vivo expansion of hematopoietic progenitor cells is not well established. The authors pursued a series of experiments to define the proper conditions for the expansion of hematopoietic cells in the short-term liquid suspension culture of mobilized peripheral blood CD34+ cells. Methods: 1.0ml cultures were initiated with 9×10^3 PB CD34+ cells, which were isolated from PB mononuclear cells (MNCs) by high-gradient cell sorting, in 12 well plates with the various combinations of hematopoietic growth factors(HGF). The following recombinant human HGFs were used: stem cell factor(SCF) 100ng/ml, granulocyte colony-stimulating factor(G-CSF) 100ng/ml, GM-CSF(granulocyte, macrophage colony-stimulating factor) 100ng/ml, interleukin-1 beta(IL-1B) 1ng/ml, interleukin-3(IL-3) 20ng/ml, interleukin-6 (IL-6) 100ng/ml. At the end of culture, colony-forming cells were evaluated by semisolid clonogenic assay. Results: 1) Using the high-gradient magnetic sorting system, CD34^+ cells were isolated with a yield of 40 3% 2) In 7 day culture of PB CD34^+ cells(9×10^3 cells), nucleated cells expanded mean 10×10^3(range, 9 to 20×10^3) with the addition of SCF alone, 35×10^3(range, 10 to 60×10^3) with SCF plus G-CSF plus GM-CSF, and 130×10^3(range, 40 to 300×10^3) with the combination of SCF, G-CSF, IL-1, IL-3, IL-6, GM-CSF. In 14 day culture, nucleated cells expanded 10×10^3 to 1,860×10^3 with combination of human hematopoietic growth factors. 3) In 10 day culture without medium change of PB CD34^+ cells, CFU-GM numbers expanded 16. 5 fold(range, 7 to 59 fold) with the addition of SCF plus G-CSF plus Il-1 plus IL-3, 31.3 fold(range, 20.5 to 101.1 fold) with the combination of SCF, G-CSF, IL-1, IL-3, GM-CSF. In 14 day culture with or without medium change of PB CD34^+ cells was inferior to 10 day culture for CFU-GM expansion. 4) There was no significant difference for CFU-GM expansion between five growth factors(SCF,G-CSF,IL-1,IL-3,GM-CSF) and six growth factors(five growth factors plus IL-6). Conclusion: The authors could confirm that short-term suspension culture of peripheral blood CD34+ cells could expand hematopoietic progenitor cells. Ten-day culture with medium change of CD34+ cells with the addition of five growth factors, i.e. SCF, G-CSF, IL-1B, IL-3, and GM-CSF, might be the most efficient in this system.

하악대구치 근심치근의 협설측 근관장의 비교

박슬희,노봉환,황호길 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.6

The aim of this study was to compare the initial apical file (IAF) length between the mesio-buccanl and mesio-lingual canals of the mandibular molar before and after early coronal flaring. Fifty mandibular molars with complete apical formation and patent foramens were selected. After establishing the initial working length of the buccal and lingual canal of the mesial root using the Root-ZX, radiographs were taken for the working length with a 0.5 ㎜ short of #15 K-file tip just visible at the foramen under a surgical microscope (OPMI 1-FC, Carl Zeiss Co. Germany) at 25X. After early coronal flaring using the K³ file, additional radiographs were taken using the same procedure. The root canal morphology and the difference in working length between the buccal and lingual canals were evaluated. These results show that the difference in the length between the mesio-buccal and mesio-lingual canals of the mandibular molar was ≤ 0.5 ㎜. If one canal has a correct working length for the mesial root of the mandibular molar, it can be used effectively for measuring the working length of another canal when the files are superimposed or loosening. In addition, the measured the working length after early coronal flaring is much more reasonable because the difference in the length between the mesio-buccal and mesio-lingual canals can be reduced.

농촌지역 오수처리시설의 성능평가 및 개선방안

박충환,박희동,이창균,임봉수 大田大學校 環境問題硏究所 2002 환경문제연구소 논문집 Vol.6 No.-

This study was carried out to evaluate performance of sewage treatment facility in rural area. Average effluent concentration was 7.6㎎/1 BOD. 10.3㎎/1 COD, 4.7㎎/1 SS, 19.140㎎/1 TN, and 1,631㎎/1 TP, within discharge quality standard. The removal efficiency rate of BOD, COD and SS was good as 89.8%. 78.5% and 90.1%, respectively. But that of TN, TP was very low as 25.0% and 31.4% respectvely. Average sewage flow rate was investigated by about 1.1㎥/d per household, 398ℓ pcd. In rainfall period, the removal efficiency rate of BOD. TN and TP was very low as 15%, 22% and 28%, respectively because of inflow and infiltration into sewer. In flowing concentration of sewage was diluted as rain is inserted into sewer and submerged facility was not operated at normal condition. Therefore it is required that the sewer will have to repair and hydraulic design for facility will have to be check. So it is necessary to support systematical, administrative measures for responsible management.

외팔보 진동의 능동제어에 관한 연구

박영필,류봉조,최환영 연세대학교 산업기술연구소 1985 논문집 Vol.17 No.1

With the development of a feedback controller for the active control of first three modes of a clampedfree beam vibration, the effects of the actuating point on the performance of the beam vibration control is examined by using optimal control theory of the state variable method. For the inaccessible states. Luenberger observer is designed for numerical analysis and experiments. Results show that(i) the damping effect of the active control is increased as the position of the actuator moves toward the free end and (ii) nodal points of each mode are the least effective points for the actuator to control the beam.

흰쥐와 햄스터의 생체리듬과 관계된 신경핵에서 Fos 면역양성물질 발현에 관한 연구

박환태,박인식,백선용,김봉선,김진정,김재봉 대한해부학회 1994 Anatomy & Cell Biology Vol.27 No.1

흰쥐 시각교차위핵에서 Galanin 면역반응 축삭종말의 분포와 신경연접구조

박환태,백선용,김봉선,김진정,김재봉 대한해부학회 1992 Anatomy & Cell Biology Vol.25 No.4

만성 간염과 간경변증의 고해상 초음파 소견

정덕환,구봉식,최종철,박병호,남경진 동아대학교의과대학 1997 동아의대학술지 Vol.9 No.2

타감작용에 의한 식생관리 방안에 관한 기초연구 : 잔디관리를 중심으로

서주환,김세천,淺野義人,박봉주 韓國植物·人間·環境學會 1998 인간식물환경학회지 Vol.1 No.2

본 연구는 난지형잔디에 의한 한지형잔디의 발아억제와 한지형잔디에 의한 잡초발생억제 등 일련의 타감작용에 의한 생태적인 잔디관리를 위한 기초자료를 제공하고자 실시되었다. turf관찰에서는 overseeding한 KB와 TF의 발아 개체수는 base의 나지형잔디에 의한 차가 거의 나타나지 않았으나, 들잔디의 KB overseeding에 있어서는 유의성이 관찰되었다. 1개체당 평균 건조중량은 base의 난지형잔디에 의한 차가 있었으며, 특히 센티피드그래스의 KB 및 TF overseeding구에서 가장 낮게 나타나 높은 생육 억제현상이 관찰되었다. 나지형잔디 5종류의 건조엽분말 50g을 이용한 pot실험에서 센티피드그래스구와 들잔디구 및 세인트어거스틴그래스구의 KB 및 TF의 발아율이 낮게 관찰돼 타감작용이 강한 것으로 나타났으며, 버뮤다그래스구와 버팔로그래스구는 양호한 발아율이 나타났다. 센티피드그래스 분말 (0, 25, 50, 75g)에 의한 KB, TF의 발아율 및 평균 건조중량을 조사한 결과 KB와 TF 발아율 및 평균 건조중량은 센티피드그래스의 건조분말이 증가할수록 감소하는 경향이 나타났다. The purpose of this study is to offer the basic materials for the ecological management of grass through allelopathy such as inhibition of cool-season turfgrasses germination by warm-season turfgrasses and retardation of weed by cool-season turfgrasses. In the observation of turf, the number of germinating Poa pratensis L. and Festuca arundinacea Schreb. was almost same but in the Poa pratensis L. overseeding, it showed significant difference. The dry weight of each individual was different by the kind of warm-season turfgrasses. Especially it is ascertained high in the Poa pratensis L.and Festuca arundinacea Schreb. overseeding of Eremochloa ophiuroides (Munro) Hack. so depression effect was showed. It was confirmed in the experiment by 50g, flour of five kinds of warm-season turfgrasses that allelopathy effected the germination percentage of Poa pratensis L. and Festuca arundinacea Schreb. slight in the plot of Eremochloa ophiuroides (Munro) Hack, Zoysia japonica Steud, Stenotaphrum secundatum (Walt) Kuntze. And the polt of Cymodon dactylon (L) Pers. and Buchloe dactyloides (Nutt.) Engeim. showed good germination. As a result of investigation of the germination percentage and the dry average weight of Poa pratensis L. and Festuca arundinacea Schreb. by Eremochloa ophiuroides (Munro) Hack. flour(0, 25, 50, 75g), the dry average weight and germination percentage of Poa pratensis L. and Festuca arundinacea Schreb. were reduced as much as Eremochloa ophiuroides (Munro) Hack. increased.

알코올 의존 환자에서 금주시간에 따른 갈망 정도와 Leptin, ACTH, Cortisol 혈중 농도의 변화와 상관 관계

김봉조,변기욱,한규희,손진욱,박철수,곽욱환 대한생물치료정신의학회 2002 생물치료정신의학 Vol.8 No.1