• Journal of KIISE:Computer Systems and Theory
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• v.34 no.11
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• pp.545-561
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• 2007

Location management and message delivery protocol is fundamental to the further development of mobile agent systems in a multi-region mobile agent computing environment in order to control mobile agents and guarantee message delivery between them. However, previous works have some problems when they are applied to a multi-region mobile agent computing environment. First, the cost of location management and message delivery is increased relatively. Second, a tracking problem arises. finally, cloned mobile agents and parent-child mobile agents do not get dealt with respect to location management and message delivery. In this paper, we present a HB (Home-Blackboard) protocol, which is a new location management and message delivery protocol in a multi-region mobile agent computing environment. The HB protocol places a region server in each region and manages the location of mobile agents by using intra-region migration and inter-region migration. It also places a blackboard in each region server and delivers messages to mobile agents when a region server receives location update form them. The HB protocol can decrease the cost of location update and message passing and solve the tracking problem with low communication cost. Also, this protocol deals with the location management and message passing of cloned mobile agents and parent-child mobile agents, so that it can guarantee message delivery of these mobile agents and pass messages without passing duplicate messages.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.124-131
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• 2005

The regulation of gene expression plays an important rolet in cell cycle controls. In this study, a novel $mas3^+$ (mitosis associated protein) gene, a homolog of human SMARCADl, was isolated and characterized from a fission yeast Schizosaccharomyces pombe. The overall homology between the helicase proteins of the two species is $87\%$. This DEAD/H box-containing molecule has seven highly conserved sequence regions that allow us to place it in the SNF2 family of the helicase superfamily. Knock-out cell of $mas3^+$ gene was constructed using kanMX6 as a selection marker. Survival of mas3 null mutant exposed to UV or MMS was similar to those of wild type cells. $mas3^+$ expression was lowest at $G_2$ and gradually increased. Cytokinesis of mas3 null mutant was abnormal at $26^{\circ}C\;and\;35^{\circ}C$ and a large number of multi-septate cells were produced. These results indicate that the $mas3^+$ is involved in cytokinesis and cell shape control.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.320-323
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• 2007

웹 서비스와 같은 분산된 환경에서, 특정 서비스를 수행하기 위해서는 원격의 컴퓨터나 사이트상에서 다중 에이전트들의 협업을 통해 이루어진다. 이때 서비스는 여러 에이전트들의 복잡한 행위들에 의해 구성된다. 또한 지능적인 서비스를 위해서는 에이전트들의 상태정보, 목적정보, 그리고 계획정보 등을 이용한다. 특히 계획정보는 에이전트들이 일련의 행위들로 구성된다. 하지만 계획수립을 위한, 기존 연구들 대부분은 정적으로 기술된 서비스 명세와 초기상태 정보를 이용하여 특정 목표를 만족시키는 단일 계획 생성 방법을 연구해왔다. 따라서 계획수립이 실행 도중에 기대하지 않은 네트워크 장애나 방해 등으로 서비스 수행을 실패하는 경우, 그 계획은 무효가 되고 다시 계획을 생성 해야만 한다. 그러나 다시 계획을 생성하기 위해서는 많은 시간을 소비하게 될 뿐만 아니라 태스크 중복이 불가피하므로 매우 비효율적이다. 이 논문에서는 강건한 계획수립과 그 계획을 실행하기 위한 효과적인 방법을 제안한다. 즉, 계획수립의 재생성을 피하기 위한 방법으로 단일 계획수립 대신에 실행 가능한 다중 계획들로 표현된 강건한 계획을 생성하는 것이다. 강건한 계획의 행위들이 실행되는 동안, 각 단계마다 실행 가능한 행위를 선택한 후, 그 행위를 실행한다. 그러나 선택된 행위가 실행결과를 낼 수 없을 경우, 대체 가능한 서브 계획 경로를 선택하여 실행한다. 강건한 계획을 표현하기 위해 페트리 넷 기반의 방법을 제안한다. 강건한 계획 생성 방법에서는 이용 가능한 모든 계획들을 입력으로 사용한다. 그 계획수립 방법은 HTN 계획수립기로 잘 알려진 JSHOP2 계획수립기내에 구현하였다. 계획 실행 방법으로는 주어진 강건한 계획에 대하여 행위들이 직접 실행하수 있도록 한다.며 용량에 의존하는 양상을 보였다. $H_2O_2$에 의해 유발(誘發)된 DNA의 손상은 catalase와 deferoxamine에 의해 억제되었지만 DPPD는 억제시키지 못했다. 배기음(排氣飮)은 $H_2O_2$에 의해 유발(誘發)된 ATP의 소실을 회복시켰다. 이러한 실험결과 $H_2O_2$에 의해 유발(誘發)된 세포(細胞)의 손상(損傷)은 지질(脂質)의 과산화(過酸化)와는 다른 독립적인 기전에 의해 일어남을 나타낸다. 결론 : 이러한 결과들로 볼 때 Caco-2 세포(細胞)에서 배기음(排氣飮)이 항산화작용(亢酸化作用)보다는 다른 기전을 통하여 Caco-2 세포안에서 산화제(酸化劑)에 의해 유발(誘發)된 세포(細胞)의 사망(死亡)와 DNA의 손상(損傷)을 방지할 수 있다는 것을 가리킨다. 따라서 본 연구(硏究)는 배기음(排氣飮)이 반응성산소기(反應性酸素基)에 의해 매개된 인체(人體) 위장관질환(胃腸管疾患)의 치료(治療)에 사용할 수 있을 가능성(可能性)이 있음을 제시하고 있다.에 이를 이용하여 유가배양시 기질을 공급하는 공정변수로 사용하였다 [8]. 생물학적인 폐수처리장치인 활성 슬러지법에서 미생물의 활성을 측정하는 방법은 아직 그다지 개발되어있지 않다. 본 연구에서는 슬러지의 주 구성원이 미생물인 점에 착안하여 침전시 슬러지층과 상등액의 온도차를 측정하여 대사열량의 발생량을 측정하고 슬러지의 활성을 측정할 수 있는 방법을 개발하였다.enin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.397-403
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• 2018

The leaves of Spiraea prunifolia were extracted with 80% aqueous MeOH and the concentrates were partitioned into EtOAc, n-BuOH, and $H_2O$ fractions. The repeated $SiO_2$ or ODS column, and medium pressure liquid chromatographies for the n-BuOH fraction led to isolation of two phenolic glucosides. The chemical structures of these compounds were determined as isosalicin (1) and crenatin (2) based on spectroscopic analyses including Nuclear magnetic resonance and MS. Extracts were analyzed using UPLC-MS/MS providing a short analysis time within 5 min using MRM technique. The concentration of crenatin was higher as 9.53 mg/g and isosalicin was lower as 0.65 mg/g. Neuroprotective effects of these compounds against hydrogen peroxide ($H_2O_2$)-induced neurotoxicity were evaluated. The results showed that exposure to $H_2O_2$ induced morphological changes, cell death and neurotoxicity in SK-N-MC cells. However, pretreatment with crenatin resulted in inhibition of morphological change, reduction of loss of cell viability and attenuation of neuronal damage. These results suggested that neuroprotective effect of crenatin isolated from S. prunifolia can be a good candidate for the development of health beneficial foods which can ameliorate the degenerative neuronal disease caused by oxidative stress.

• Pediatric Infection and Vaccine
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• v.22 no.2
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• pp.97-105
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• 2015

Purpose: Serotyping pneumococcal isolates is important to monitor efficacy of pneumococcal vaccines. Because of difficulties of typing pnueumocci, a multiplex bead-based (multibead) serotyping assay was recently introduced. The aim of this study is to establish a new multibead serotyping assay and to apply this method to analyze clinical isolates of pneumococci in Korea. Methods: To establish the multibead serotyping assay, six key reagents were transferred from University of Alabama at Birmingham (UAB) to Ewha Center for Vaccine Evaluation and Study (ECVES): bead set coated with polysaccharide and monoclonal antibody pool were used in one multiplex inhibition-type immunoassay and 2 bead sets coated DNA probe and 2 primer pools were used in two multiplex PCR-based assays. After multibead serotyping assay was set up, 75 test samples of pneumococci were analyzed whether ECVES is able to identify serotype correctly. After confirming the performance, serotyping assay was applied to identify serotypes of 528 clinical isolates of pneumococci collected from 3 different hospitals. Results: After establishment of the multibead pneumococcal serotyping assay system at ECVES, 75 test samples were analyzed. There was no discrepancy of serotypes of 75 test samples between the results assigned at UAB and those at ECVES. The serotypes of 528 pneumococci isolated from patients or healthy subjects were determined in 94.3% of isolates (498/528). Conclusions: The multibead pneumococcal serotyping assay can be successfully established in Korea. With this method, surveillance of serotypes of pneumococci isolated from patients as well as healthy subjects could be studied.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.3
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• pp.211-221
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• 2014

Purpose: The purpose of this study was to evaluate the surface characteristics and response of osteoblast-like cell at SLA surface treated with NaOH. Materials and methods: Three kinds of specimens were fabricated for the experiment groups. Control group was a machined surface, SLA group was a conventionally SLA treated surface, and SLA/NaOH gorup was SLA surface treated with NaOH. To evaluate the surface characteristics, the surface elemental composition (XPS), surface roughness and surface contact angle were evaluated in each group. And the cytotoxicity, cell adhesion, cell proliferation and ATP activity of osteoblast-like cells (MG-63 cells) were compared in each group for evaluatation of the cell responses. Statistical comparisons between groups were carried out via one-way ANOVA using the SPSS software (SPSS Inc., Chicago, USA), and then performed multiple comparisons. The differences were considered statistically significant at P<.05. Results: SLA surface treated with NaOH (SLA / NaOH group) was changed to hydrophilic surface. All groups did not show the cytotoxicity to the MG-63. In cell adhesion studies, SLA / NaOH group showed the higher degree of adhesion than anothers (P<.05), Up to 7 days of incubation, the proliferation was showed the increasing tendency in all groups but SLA / NaOH group showed the highest cell proliferation between the three groups (P<.05). At 7 days of incubation, there was no difference in ALP activities between the three groups, but at 14 days, SLA / NaOH group showed significant increase in ALP activities (P<.05). Conclusion: In this study, SLA surface treated with NaOH promoted cell adhesion, proliferation and differentiation. It means that SLA/NaOH group is possible to promote osseointegration of implants.

• Journal of Life Science
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• v.20 no.1
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• pp.103-112
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• 2010

Pemetrexed has demonstrated clinical activity in non-small cell lung cancer (NSCLC) as well as other solid tumors. It transports into the cells via reduced folate carrier (RFC) and is polyglutamated by folypolyglutamate synthetase (FPGS). Pemetrexed directly inhibits several folate-dependent enzymes such as thymidylate synthase (TS), dihydrofolate reductase (DHFR), and glycinamide ribonucleotide formyltransferase (GARFT). We investigated the effects of genetic variations and the expression of RFC, FPGS, TS and DHFR enzymes on drug sensitivity to pemetrexed in NSCLC cells. Polymorphisms in RFC, FPGS, and DHFR were genotyped in four NSCLC cells - A549, PC14, HCC-1588, and H226. Real-time RT-PCR and Western blot was performed to evaluate mRNA transcripts and protein of these genes. The cytotoxicity of pemetrexed was measured by SRB assay. In PC14 and H226 cells, increased mRNA expressions of RFC and FPGS were associated with higher cytotoxicity to pemetrexed. 2R/2R genotype of TS and its increased mRNA expression were associated with drug resistance to pemetrexed in A549 cells, whereas 3R/3R genotype in TS with decreased mRNA expression was associated with higher sensitivity in H226 cells. After pemetrexed treatment, an inverse change of DHFR mRNA and protein expression was found. The strongest linkage disequilibrium (LD) was discovered between-1726C>T and -1188A>C SNP of DHFR gene. Our findings suggest the cytotoxic effect of pemetrexed may be associated with genetic polymorphisms and the expression level of genes involved in pemetrexed metabolisms in NSCLC cells.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.104-112
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• 2012

Recently, the HDR imaging technique that mimics human eye is incorporated with LCD/LED display devices to deal with mismatch between the real world scene and the displayed image. However, HDR image has a veiling glare limit as well as a scale of the local contrast problem. In order to overcome these problems, several color correction methods, CSR(center/surround Retinex), MSR (Multi-Scale Retinex), tone-mapping method, iCAM06 and so on, are proposed. However, these methods have a dominated color throughout the entire resulting image after performing color correction. Accordingly, this paper presents a new color correction method using dynamic cone response function. The proposed color correction method consists of tone-mapping and dynamic cone response. The tone-mapping is obtained by using a linear interpolation between chromatic and achromatic. Thereafter, the resulting image is processed through the dynamic cone response function, which estimates the dynamic responses of human visual system as well as deals with mismatch between the real scene image and the rendered image. The experiment results show that the proposed method yields better performance of color correction over the conventional methods.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.8
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• pp.1063-1071
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• 1999

Fine grid calculations are reported for the developing turbulent flow in a curved duct of square cross-section with a radius of curvature to hydraulic diameter ratio ${\delta}=Rc/D_H=3.357 $ and a bend angle of 720 deg. A sequence of modeling refinements is introduced; the replacement of wall function by a fine mesh across the sublayer and a low Reynolds number algebraic second moment closure up to the near wall sublayer in which the non-linear return to isotropy model and the cubic-quasi-isotropy model for the pressure strain are adopted; and the introduction of a multiple source model for the exact dissipation rate equation. Each refinement is shown to lead to an appreciable improvement in the agreement between measurement and computation.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.118.2-118.2
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• 2016

몇몇의 박테리아들은 바이오필름을 형성하여 그들 스스로를 보호한다. 하지만 바이오필름으로 인해 악취와 질병 등의 문제가 많이 발생되고 있기 때문에 바이오필름을 형성하는 박테리아의 성장을 효율적으로 억제하기 위해 은 나노, 구리 나노입자들이 포함된 다양한 나노스케일의 재료들에 대한 연구가 활발히 진행되어오고 있다. 이들 연구의 주된 목표는 체내에서 독성은 나타내지 않으면서 항균성을 증가시키는 것에 있다. 특히, 구형으로 이루어진 나노입자와 높은 종횡비를 가지는 탄소나노튜브와 같이 차원이 다른 나노물질들의 복합체들은 세포독성을 최소화하면서 특정 박테리아에 대한 항균성을 향상시킬지도 모른다. 이번 연구에서는, 산 처리된 탄소나노튜브에 화학적인 방법을 이용하여 구리 이온을 각각 환원시켜 구리 나노-탄소나노튜브 복합체를 합성하였다. 이들 복합체는 transmission electron microscopy, X-ray diffractometry, energy-dispersive X-ray spectroscopy 를 이용하여 특성이 분석되었고 Methylobacterium spp., Sphingomonas spp. 와 E. coli 에 대하여 항균성이 평가되었다. 추가적으로 구리 나노-탄소나노튜브 복합체는 human fibroblast cells 에 대하여 세포독성이 평가되었고 제작된 마이크로칩 안에 형성된 바이오필름의 성장억제효과가 평가되었다. 결과적으로, 구리 나노-탄소나노튜브 복합체에서 바이오필름을 형성하는 Methylobacterium spp. 에 대하여 특이적으로 항균성을 나타냈으며 바이오필름이 형성된 마이크로칩에서 바이오필름을 제거 하는 것이 확인되었다.