• Nuclear Engineering and Technology
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• v.35 no.2
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• pp.91-107
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• 2003

Since DBA(Design Basis Accidents) has been studied rather separately from SA(Severe Accidents) in the conventional nuclear reactor safety analysis, the thermal hydraulics during transition between DBA and SA has not been identified so much as each accident itself. Thus, in this study, the thermal hydraulic behavior from DBA to the commencement of SA has been experimentally and analytically investigated for the long-term cooling phase of LB-LOCA(Large-Break Loss-of-Coolant Accident). Experiments were conducted for both cases of the loop seal open and closed in an integral test loop, named as SNUF (Seoul National University Facility), which was scaled down to l/6.4 in length and 1/178 in area of the APR1400 (Advanced Power Reactor 1400MWe). The core mixture level was a main measured value since it took major role in the fuel heat-up rate, the location of fuel melting initiation and the channel blockage by melting material during SA. Experimental results were compared to MAAP4.03 to assess its model of calculating the core mixture level. MAAP4.03 overestimates the core two- phase mixture level because sweep-out and spill-over and the measures to simulate the status of loop seal are not included, which is against the conservatism. Thus, it is recommended that MAAP4.03 should be improved to simulate the thermal hydraulic phenomena, such as sweep-out, spill-over and the status of loop seal.

• Journal of Acupuncture Research
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• v.17 no.1
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• pp.287-318
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• 2000

The purpose of this study is to observe the effect of Aqua-acupuncture utilizing Lycopi Herba Solution(LH-AS) on arthritis. For that purpose, we formed three experimental group, synovial cells of human body, normal BALB/C mice and DBA/1J mice with collagen II-induced arthritis, and measured the treatment effect of LH-AS on each group. The conclusions are as follows. 1. After the LH-AS treatment on synovial cells, there were no significant change in 1, 10, 50 and $100{\mu}g/m{\ell}$ whereas there was significant change in 200 and $400{\mu}g/m{\ell}$ in cytotoxicity. 2. IL-6, IL-$1{\beta}$, TNF-${\alpha}$ gene expression of synovial cells and the secretion amount of IL-6 and IL-$1{\beta}$ are significantly inhibited in treatment group with LH-AS. 3. The proliferation of synovial cells was significantly inhibited in treatment group with rIL-6, LH-AS 200 and rIL-6, $100{\mu}g/m{\ell}$. 4. After the DBA/1J mice with collagen II-induced arthritis were treated by LH-AS, the incidence of arthritis, hind paw edema, the index of arthritis and DTH were significantly inhibited. 5. After the DBA/1J mice with collagen II-induced arthritis were treated by LH-AS, splenetic weight was significantly increased and the number of leukocyte was significantly decreased. But there was no significant change in the number of platelet. 6. After the DBA/1J mice with collagen II-induced arthritis were treated by LH-AS, the number of $CD4^+$, $CD8^+$ activated cells and the surface-receptor expression were significantly increased whereas the number of $CD19^+$ activated cells and the surface-receptor expression were decreased. 7. After the DBA/1J mice with collagen II-induced arthritis were treated by LH-AS, total protein, LDH were significantly decreased, but there was no significant change in creatinine. 8. After the normal splenetic cells of BALB/C mice were treated by LH-AS and cultured, it was observed that the adherent cells were morphologically activated and IL-12 and IFN-${\gamma}$ gene expression were increased. 9. After the normal splenetic cells of BALB/C mice were treated by LH-AS and cultured, the number of $CD4^+$, $CD8^+$, $CD19^+$ activated cells and surface-receptor expression were inhibited when being compared with the control group. Taking all these observations into account, LH-AS injection is considered to be effective in treating arthritis and put to practical use in future arthritis clinic.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.94-103
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• 2006

Ethernet passive optical network (EPON) has drawn many attention as a promising access network technology for FTTH because it can provide a high bandwidth with a low cost. Since the uplink bandwidth in the EPON system is shared by many users, it is necessary for an EPON system to have an efficient bandwidth allocation mechanism. To support QoS in EPON, the previous bandwidth allocation schemes employ strict priority queueing (SPQ). Since SPQ gives unlimited priority to higher service class, the QoS of lower service classes gets worse. In this paper, we propose Class Gated DBA (Dynamic Bandwidth Allocation) algorithm in which the bandwidth is requested / granted in a service class basis. To avoid the monopoly in bandwidth usage by higher classes the maximum bandwidth that is allocate to each service class is limited (fairness between services classes). In addition, to avoid the monopoly in bandwidth usage by some particular users, each ONU runs fairness bandwidth allocation algorithm within each service classes. Through computer simulations, it is verified that the proposed algorithm achieves a good level of QoS, and at the same time maintains a good level of fairness between both service classes and users.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.315-324
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• 2010

The effect of beta-glucan ($Polycan^{TM}$) derived from Aureobasidium pullulans SM-2001 were observed on, collagen-induced rheumatoid arthritis (RA) in DBA mice. Six week-old male DBA/1J mice were immunized by the intradermal injection of $200\;{\mu}g$ of bovine type II collagen with the equal volume of complete Freund's adjuvant at the tail base on day 1. On day 21, the mice were boosted by the intradermal injection of $200\;{\mu}g$ of bovine type II collagen with incomplete Freund's adjuvant. From the first immunization, mice had been administered $Polycan^{TM}$ (21.25, 42.5 and 85 mg/kg), diclofenac and vehicle once a day for 4 weeks, respectively. Collagen-induced hyperimmunities and arthritis signs were markedly and dose-dependently inhibited by treatment of $Polycan^{TM}$ compared with RA control except for tibial cartilages of $Polycan^{TM}$ 21.25 group. $Polycan^{TM}$ effectively inhibited the histopathological changes of collagen-induced arthritis and hyper-immunities.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.3
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• pp.277-291
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• 2023

This study aimed to compare the effects of applying different types of dentin bonding agents (DBAs) on tooth and on the sealing ability of CSC in regenerative endodontic procedures (REPs). Specimens were made from 120 human first premolars and categorized into the following groups based on the presence and the type of DBA: Group I, no bonding; Group II, One-Step; Group III, Clearfil SE Bond; and Group IV, Single Bond Universal. Subsequently, the groups were categorized into Subgroup a and Subgroup b, in which Endocem MTA^® Premixed Regular and Biodentine were used, respectively. The CIE L^*a^*b^* on the photos taken prior to TAP placement (S0), 1 week after TAP placement (S1), 2 weeks after TAP placement (S2), 4 weeks after TAP placement (S3) and 2 weeks after CSC placement (S4) was used to assess discoloration. The samples were submerged in a 2% methylene blue solution and magnified by 30 times under a stereomicroscope to assess microleakage. The application of DBA during REP reduced crown discoloration, while Biodentine showed minimal discoloration with or without DBA and regardless of the DBA type. Additionally, the application of DBA did not increase microleakage.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.192-192
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• 1994

본 논문에서는 cytochrome P450 LA1 유전자의 5'-upsteam 조절부위의 클로닝을 실시하였다. pUC19 vector에 연결시킨 3.4 Kb 크기의 Pstl DNA조각을 Sst1, Nco1 제한 효소로 자른 뒤, Exonuclease III 를 처리하여 약 200bp 씩의 차이를 갖는 여러 크기의 plasmid들을 얻었다. 이 plasmid 의 핵산서열을 알아보기 위해 dideoxy nucletide를 이용한 sequencing방법으로 그 핵산서열의 결정 실험을 시도하였다. 또한, 다환상 방향족 탄화수소 화합물에 반응성을 갖는 C57BL/6N 생쥐와 반응성을 갖지않는 DBA/2N 생쥐에 있어 phase II 대사 효소인UDP-glucuronosyltransferase 효소활성에 대한 3-methylcholanthrene의 영향을 알아보기 위해 C57BL/6N 생쥐와 DBA/2N 생쥐에 각각 다른 농도의 3-methylcholanthrene을 처리하거나 각기 다른 시간에 3-methylcholanthrene를 처리하였다. 그 결과 UDP-glucuronosyl-transferase의 mRNA가 3-methylcholanthrene양의 증가에 따라, 처치시간이 길어짐에 따라 증가되어지며 그 mRNA위 크기는 약 2.2Kb 정도임을 알았다. 이로부터 UDP-ghucuronosyltransferase 또한 cytochrome P45O와 함께 다환상 방향족 탄화수소 화합물 조절인자를 통한 조절을 받을 것이며 phase I phase II 약물 대사 효소가 조절상 밀접한 관련을 가짐을 예측할 수 있었다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.83-83
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• 2001

Head of Panax ginseng indicates its growth number of years and it has been widely used for supplying energy to weak person. However, the underlying mechanisms are not sufficiently reported. Thus, we inclined to study head of Panax ginseng in rheumatoid arthritis and inflammation. Rheumatoid arthritis (RA), an organ-specific inflammatory disease of human, is characterized by a chronic and destructive inflammatory reaction and possibly autoimmune in etiology. It is occurred when the synobial membranes of joints and many other tissues of the body is attacked which induces significant health problem in terms of numbers of sufferers (U.S. incidence 23.7/100,000), and the synobial inflammatory is dominated by activated macrophage.

• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.469-481
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• 2004

In this paper, we investigate the mean queue length and the mean packet delay of a dynamic bandwidth allocation(DBA) scheme in an Ethernet passive optical network(EPON). We focus on the interleaved polling system with a gated service discipline. We assume that input packets arrive at an optical network unit(ONU) according to Poisson process. We use a continuous time queueing model in order to find the queue length distribution of the gated interleaved polling system with the first stage input queue and the second stage transmission queue. We give some numerical results to investigate the mean queue lengths and mean packet delays for the symmetric polling system with statistically identical stations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.743-744
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• 2013

This paper proposes a new DBA (dynamic bandwidth allocation) algorithm for a TWDM PON (time and wave-division multiplexing passive optical network) which is based on XGPON (10-Gigibit-Capable PON). Modifying a DBA algorithm of an XGPON, the proposed algorithm not only allocates the transmission slot but also assigns a wavelength to use for each ONU.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.1169-1172
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• 2003

Ethernet 에서의 트래픽 제어 방식은 구현 및 제어가 용이한 최선형이 일반적인데, 이 경우 QoS 보장이 어려워 최근에는 Ethernet 에서도 광대역 및 QoS 등이 망 발전의 새로운 지표가 되면서 EPON 에서도 QoS 기반 DBA 연구가 진행되고 있다. 대부분의 QoS 기반 제어는 각 연결의 대역 및 지연 등의 서비스 특성에 따라 제어가 이루어지며, 연결별로 요구된 대역이 동일 ONU의 다른 연결 또는 다른 ONU의 연결들의 트래픽에 영향을 받지 않도록 보장되는 방식으로 제어가 복잡하다. 본 연구에서는 최선형 서비스에 기반을 두고, OLT 에서 각 ONU 의 연결대역별로 제어하지 않고 각 ONU 의 트래픽 특성을 서비스의 우선 순위에 적용하여 제어함으로써 간단한 제어로 실시간 서비스의 QoS 를 만족시킬 수 있는 DBA 방식을 제안하며, 또한 하향 트래픽에 따른 상향 트래픽의 영향을 분석하였다.