• Journal of applied mathematics & informatics
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• 제14권1_2호
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• pp.319-328
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• 2004

In this paper we investigate the qualitative behaviour of numerical approximation to a class delay differential equation. We consider the numerical solution of the delay differential equations undergoing a Hopf bifurcation. We prove the numerical approximation of delay differential equation had a Hopf bifurcation point if the true solution does.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.143-144
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• 2006

This paper presents an adaptive OFDM system with multistep predictor to effectively compensate multiple feedback delays. The proposed scheme adaptively changes the modulation order per subcarrier based on the predicted CSI to improve data capacity and system performance.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2006년도 추계학술대회 학술발표 논문집 제16권 제2호
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• pp.243-246
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• 2006

본 논문에서는 모발내에 있는 약 30여가지의 생체 미네랄과 8가지의 중금속 정보 분석을 통해 생체내에 양양상태의 과잉, 결핍 및 불균형 상태를 평가하고, 그 결과가 현재 생체에 미치는 영향을 예측하여, 건강을 유지하는 방향을 제시할 수 있는 의료용 지능적 의학진단 시스템을 구축하였다. 이 논문에서는 생체내 미네랄 정보를 다중 퍼지규칙베이스 시스템으로 구축함으로써 환자에게 보다 효율적으로 치료와 예방방법을 제시할 수 있는 의학진단시스템을 구축하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.65.1-65.1
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• 2003

Natural benzo[c]phenanthridine and protoberberine alkaloids which have been attractive to synthetic organic chemists and biochemists over the last 2 decades since such compounds have shown interesting biological properties such as antitumor, antiviral and antimicrobacterial activities. For the systematic research on these alkaloids, several total syntheses of these alkaloids have been reported. However, the bulk of reported benzo[c]phenanthridine synthetic studies to date have involved multistep sequences for assembly of the target molecules as well as lack of generality for synthesizing substituted molecules. (omitted)

• 한국발생생물학회지:발생과생식
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• 제27권4호
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• pp.167-174
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• 2023

Development of hepatocellular carcinoma (HCC) is driven by a multistep and long-term process. Because current therapeutic strategies are limited for HCC patients, there are increasing demands for understanding of immunotherapy, which has made technological and conceptual innovations in the treatment of cancer. Here, I discuss HCC immunotherapy in the view of interaction between liver resident cells and immune cells.

• 대한한방내과학회지
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• 제22권4호
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• pp.639-645
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• 2001

Angiogenesis is a fundamental process in reproduction and wound healing. Under these condition, neovascularization is tightly regulated. Unregulated angiogenesis may lead to several angiogenic diseases, and is thought to be indispensible for solid tumor growth and metastsis. The construction of new vascular network is a multistep cascade involving basement membrane degradation, endothelial cell proliferation, endothelial cell migration, and tube formation. Newly reported anti-angiogenic agents in oriental medical field have targeted both specific and multistep stages in the angiogenic process. From recent approach in oriental medical field with several herb medicines including activating blood flow and removing blood stasis medicine(活血化瘀藥), it may be possible in the future to develope specific anti-angiogenic agents that offer a less toxic potential therapy for cancer and angiogenic disease.

• Journal of Microbiology and Biotechnology
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• 제28권11호
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• pp.1850-1858
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• 2018

Glucosamine (GlcN) is widely used in the nutraceutical and pharmaceutical industries. Currently, GlcN is mainly produced by traditional multistep chemical synthesis and acid hydrolysis, which can cause severe environmental pollution, require a long prodution period but a lower yield. The aim of this work was to develop a whole-cell biocatalytic process for the environment-friendly synthesis of glucosamine (GlcN) from N-acetylglucosamine (GlcNAc). We constructed a recombinant Escherichia coli and Bacillus subtilis strains as efficient whole-cell biocatalysts via expression of diacetylchitobiose deacetylase ($Dac_{ph}$) from Pyrococcus furiosus. Although both strains were biocatalytically active, the performance of B. subtilis was better. To enhance GlcN production, optimal reaction conditions were found: B. subtilis whole-cell biocatalyst 18.6 g/l, temperature $40^{\circ}C$, pH 7.5, GlcNAc concentration 50 g/l and reaction time 3 h. Under the above conditions, the maximal titer of GlcN was 35.3 g/l, the molar conversion ratio was 86.8% in 3-L bioreactor. This paper shows an efficient biotransformation process for the biotechnological production of GlcN in B. subtilis that is more environmentally friendly than the traditional multistep chemical synthesis approach. The biocatalytic process described here has the advantage of less environmental pollution and thus has great potential for large-scale production of GlcN in an environment-friendly manner.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2265-2268
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• 2013

Several lines of evidence indicate that cancer is a multistep process. To survey the mechanisms involving gene alteration and miRNAs in adrenocortical cancer, we focused on transcriptional factors as a point of penetration to build a regulatory network. We derived three level networks: differentially expressed; related; and global. A topology network ws then set up for development of adrenocortical cancer. In this network, we found that some pathways with differentially expressed elements (genetic and miRNA) showed some self-adaption relations, such as EGFR. The differentially expressed elements partially uncovered mechanistic changes for adrenocortical cancer which should guide medical researchers to further achieve pertinent research.

• 호남수학학술지
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• 제32권3호
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• pp.481-491
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• 2010

In this paper, we investigate a generalization of the Adams-Bashforth method by using the Taylor's series. In case of m-step method, the local truncation error can be expressed in terms of m - 1 coefficients. With an appropriate choice of coefficients, the proposed method has produced much smaller error than the original Adams-Bashforth method. As an application of the generalized Adams-Bashforth method, the accuracy performance is demonstrated in the satellite orbit prediction problem. This implies that the generalized Adams-Bashforth method is applied to the orbit prediction of a low-altitude satellite. This numerical example shows that the prediction of the satellite trajectories is improved one order of magnitude.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.963-970
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• 2012

We review novel chemical kinetics proposed for quantitative description of fluctuations in reaction times and in the number of product molecules in a heterogeneous biological system, and discuss quantitative interpretation of randomness parameter data in enzymatic turnover times of ${\beta}$-galactosidase. We discuss generalization of renewal theory for description of chemical fluctuation in product level in a multistep biopolymer reaction occurring in a dynamically heterogeneous environment. New stochastic simulation results are presented for the chemical fluctuation of a dynamically heterogeneous reaction system, which clearly show the effects of the initial state distribution on the chemical fluctuation. Our stochastic simulation results are found to be in good agreement with predictions of the analytic results obtained from the generalized master equation.