• 정보보호학회논문지
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• 제32권5호
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• pp.869-879
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• 2022

본 연구를 통해 매우 대중적인 압축 알고리즘인 Deflate 알고리즘을 통해 생성되는 3가지 유형의 압축 데이터 블록 가운데 원본 데이터 없는 비 압축 블록(No-Payload Non-Compressed Block;NPNCB) 유형을 임의로 생성하여 정상적인 압축 블록 사이에 미리 설계된 공격 시나리오에 따라 삽입하는 방법을 통해 악의적 코드 또는 임의의 데이터를 은닉하는 취약점을 발견하였다. 비 압축 블록의 헤더에는 byte align을 위해서만 존재하는 데이터 영역이 존재하며, 본 연구에서는 이 영역을 DBA(Disposed Bit Area)라고 명명하였다. 이러한 DBA 영역에 다양한 악성 코드와 악의적 데이터를 숨길 수 있었으며, 실험을 통해 정상적인 압축 블록들 사이에 오염된 블록을 삽입했음에도 기존 상용 프로그램에서 정상적으로 경고 없이 압축 해제 되었고, 악의적 디코더로 해독하여 악성 코드를 실행할 수 있음을 보였다.

• The Journal of Asian Finance, Economics and Business
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• 제7권12호
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• pp.275-282
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• 2020

The objectives of this study are to understand the meaning of cloud accounting, to investigate whether it is favorable for performance of the organization and what are the challenges if a country like Bangladesh wants to implement it. Primary data have been collected from 300 respondents selected from the field of accounting, such as accountants, accounting graduates of different universities, teachers and bankers. To measure the reliability and validity of the sample size and data, KMO and Bartlett's test have been adopted and the results proved to be reliable and valid for the study. Regression analysis has been done to find out the positive impact of cloud accounting on organizational performance and negative impact of cloud accounting on existing accounting system of the organization. The results of regression analysis supported our alternative hypotheses that cloud accounting can improve organizational performance, but it has also some negative impacts. Descriptive statistics have been used to find out the probable challenges that may be faced by organizations that want to implement it. This is a pioneering study because there is little research on this topic, thus it is expected to develop awareness about cloud accounting in field of accounting in Bangladesh.

• 동의생리병리학회지
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• 제18권5호
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• pp.1471-1475
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• 2004

Thuja orientalis extract (TOS) has been used on the hemostatic roborant, sedatives and stressless in oriental countries. We investigate the inhibitory effects on the productions of pro-inflammatory cytokines such as interleukin-1beta (IL-1β), IL-6, tumour necrosis factor alpha (TNF-α), and nitric oxide (NO) and the hair promotiont of TOS in the macrophage celline RAW264.7 or hair loss-induced DBA1J mice. T08 (50-500 ㎍/㎖) per se had no cytotoxic effect non-stimulated cells, but this extracts concentration-dependently reduced the release of NO, (IL-1β), IL-6, and TNF-α in the stimulate RAW264.7 cells with lipopolysaccharide (LPS). Moreover, when applied TOS (500 ㎍/㎖) to DBA 1J/mice, hair growth was promoted remarkably. These data suggest that T08 promotes hair growth on hair loss induced model mice and these properties may contribute to the anti- hair loss activity of the Thuja orientalis.

• 한국통신학회논문지
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• 제28권11B호
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• pp.1023-1030
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• 2003

본 논문에서는 서로 다른 요구조건을 갖는 응용 서비스들을 지원하는 가입자 접속망에서 서비스 고유의 서비스 품질을 효과적으로 지원하기 위한 대역 할당 방안을 다룬다. 음성 및 실시간 비디오 등의 지연에 민감한 실시간 트래픽과 데이터 및 BE(Best Effort)와 같은 비 실시간 트래픽 등 다중 응용 서비스를 지원해야 하는 EPON(Ethernet Passive Optical Network)망에서 상향 트래픽의 동적 대역 할당방안에 대하여 논하기로 한다. 구조적으로 제한된 자원 환경에서 상향 전송 대역을 효율적으로 사용하고, 실시간 트래픽의 지연성능을 향상하는 새로운 방안을 제안하고, 시뮬레이션으로 제안된 방안의 지연성능을 분석한다.

• ETRI Journal
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• 제26권4호
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• pp.321-331
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• 2004

In this paper, we propose a new dynamic bandwidth allocation (DBA) algorithm for multimedia services over Ethernet PONs (passive optical networks). The proposed algorithm is composed of a low-level scheduler in the optical network unit (ONU) and a high-level scheduler in the optical line terminal (OLT). The hierarchical DBA algorithm can provide expansibility and efficient resource allocation in an Ethernet PON system in which the packet scheduler is separated from the queues. In the proposed DBA algorithm, the OLT allocates bandwidth to the ONUs in proportion to the weight associated with their class and queue length, while the ONU preferentially allocates its bandwidth to queues with a static priority order. The proposed algorithm provides an efficient resource utilization by reducing the unused remaining bandwidth caused by the variable length of the packets. We also define the service classes and present control message formats conforming to the multi-point control protocol (MPCP) over an Ethernet PON. In order to evaluate the performance, we designed an Ethernet PON system on the basis of IEEE 802.3ah "Ethernet in the first mile" (EFM) using OPNET and carried out simulations. The results are analyzed in terms of the channel utilization, queuing delay, and ratio of the unused remaining bandwidth.

• Biomolecules & Therapeutics
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• 제15권4호
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• pp.235-239
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• 2007

In order to evaluate the improvement effects of head of Panax ginseng on chronic arthritis, we have investigated the activity of butanol fraction (BuOH fraction) in vitro and in vivo system. BuOH fraction showed significant inhibition on the elastase activity. Anti-arthritic activity of BuOH fraction was also examined on type II collagen-induced arthritis in DBA/1J mice. Mice were immunized with injection of type II collagen emulsified in Freund's complete adjuvant, followed by a booster injection 21 days later. BuOH fraction(BHPG) was administered at an oral dose of 500mg/kg for 2 weeks from the 1st day boost. The hind paw edema was significantly decreased in the group of treatment with BuOH fraction compared to control. In collagen-induced DBA/1J mice, BuOH fraction did not affected the collagen antibody titer but significantly inhibited the tumor necrosis factoralpha(TNF-${\alpha}$) activity. These results were confirmed with histological evaluation of joint tissues. This study may raise the possibility that the usage of BuOH fraction of head of Panax ginseng as alternative medicine for the relief and prevention of rheumatoid arthritis symptoms.

• 대한수의학회지
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• 제36권3호
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• pp.531-539
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• 1996

The lectin-binding patterns in the testis of the sexually matured Jindo dog were investigated to study the distribution of glycoconjugates in the seminiferous tubule under light and transmission electron microscopy. Positive reactions to Wheat germ agglutinin(WGA) and Dolichos biflorus agglutinin (DBA) were observed in the Sertoli cell and in the residual body of spermatid with a stronger reaction in the Sertoli cell to the lectins than in the residual body. Strong reactions to Soybean agglutinin(SBA) and Peanut agglutinin(PNA) were observed in the acrosome vesicles of the Golgi- and cap-phase spermatid, while a moderate reaction was observed in the acrosome-phase, maturation-phase spermatid and the residual body. The acrosome area of the spermatid reacted intensively to Griffonia simplicifolia agglutinin( GS-I) when the cell was in the acrosome-phase and maturation-phase, and the same reaction to the GS-I was observed in the residual body. However, the seminiferous tubule did not react to Ulex europeus agglutinin I(UEA-I). The gold-labelling of the Sertoli cells with DBA resulted in positive reactions of the Sertoli cell column and processes when observed under the electron microscopy, while the Golgi-, cap- and acrosome-phase spermatids reacted positively to SBA in the peripheral low-dense area of the acrosome vesicle of spermatid. Based on these results, we concluded that differences in the lectin-binding pattern of the seminiferous tubules were recognized in the Jindo dog compared to other animals.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.381-381
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• 2000

Lectin binding assay was conducted on 3 A. tamarense isolates (AT-A, AT-2 and AT-6). Fatty acid composition of all 3 isolates was analyzed, and total carotenoid content and $\beta$-carotene were also determined. AT-A and AT-2 treated with different lectins in this study showed the positive response, whereas potentially toxic AT-6 did not bind DBA lectin, regardless of different growth phase, but conjugated ConA, PNA, RCA, SBA, UEA and WGA. It is possible that DBA is a desirable method for rapid and easy discrimination of highly toxic A. tamarense. AT-A, AT-2 and AT-6 comprised saturated fatty acids (49.0-61.9%), monounsaturated fatty acids (8.0-20.5%) and polyunsaturated fatty acids (23.2-30.5%). In particular, 22:6 (n-3) polyunsaturated fatty acid in AT-6 had a high abundance, compared with AT-A and AT-2. However, carotenoid content and $\beta$-carotene were not contributed to discriminate each isolate. Due to variability in biochemical composition at different isolates, possibly DBA and 22:6 (n-3) polyunsaturate fatty acid provide a good information for discrimination of AT-6.

• 한국통신학회논문지
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• 제28권7B호
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• pp.620-627
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• 2003

EPON망은 중앙 기지국과 가입자들 사이에 광 액세스 라인을 저렴하게 제공할 수 있는 액세스 망 기술로 떠오르고 있다. 동적 대역 할당은 상향 채널의 효율적인 활용을 위해 ONU간 통계적 다중화를 제공한다. 본 논문에서는 EPON망에서 차등 CoS를 제공하기 위해 주기적 폴링을 기반으로 한 동적 대역 할당 방법을 제안한다. 더불어, Interleaved 폴링 방식에 기반한 동적 대역 할당 방안은 상향 트래픽 로드가 적은 경우 하향 채널의 용량을 대폭 감소시키는 단점을 가지고 있음을 보인다. 실제적인 시뮬레이션 결과를 얻기 위해 self-similarity와 long-range dependence 특성을 갖는 트래픽을 이용하였다. EPON망의 성능은 ONU에 제공되는 다양한 로드별로 분석하였으며, 특히 차등 CoS 특성 분석을 위해 등급별 패킷의 지연 특성을 분석하였다.

• Nuclear Engineering and Technology
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• 제35권2호
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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.