• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.406-409
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• 1997

The various cobalt(Ⅱ) complexes were synthesized and characterized using tris-(2-benzimidazolylmethyl)amine (ntb) as a ligand where the ntb plays as a tripodal tetradentate ligand to form complexes with a trigonal pyramidal geometry. The complexes have 5 and 6 coordinate cobalt(Ⅱ) ions depending on the additional ligand used. In each complex the additional ligand, chloride anion, or acetate anion occupies the "open" site trans to the apical tertiary nitrogen atom of ntb ligand. Complex 1, [Co(Ⅱ)(ntb)Cl]Cl has a trigonal bipyramidal geometry. This geometry was easily constructed using ntb as a tetradentate ligand and chloride as a monodentate ligand. The complex is isostructural to the corresponding manganese(Ⅱ) complex. Crystal data are as follows: [Co(Ⅱ)(ntb)Cl]Cl·MeOH, 1. triclinic space group P1; a=13.524(2) Å, b=14.037(2) Å, c=17.275(1) Å; α=78.798(9), β=84.159(8)°, γ=65.504(9)°; V=2929.6(6) Å3; Z=4; R1=0.0715, wR2=0.1461 for reflections of I > 2σ(I). Six coordinate complex 2 [Co(ntb)(OAc)](OAc) was synthesized using ntb as a tetradentate ligand and acetate as a bidentate chelating ligand.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.3
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• pp.65-72
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• 2019

HPC(High Performance Computing) is the computing system that connects a number of computing nodes with high performance interconnect network. In the HPC, interconnect network technology is one of the key player to make high performance systems, and mainly, Infiniband or Ethernet are used for interconnect network technology. Nowadays, PCIe interface is main interface within computer system in that host CPU connects high performance peripheral devices through PCIe bridge interface. For connecting between two computing nodes, PCIe Non-Transparent Bridge(NTB) standard can be used, however it basically connects only two hosts with its original standards. To give cost-effective interconnect network interface with PCIe technology, we develop a prototype of interconnect network system with PCIe NTB. In the prototyped system, computing nodes are connected to each other via PCIe NTB interface constructing switchless interconnect network such as ring network. Also, we have implemented prototyped data sharing mechanism on the prototyped interconnect network system. The designed PCIe NTB-based interconnect network system is cost-effective as well as it provides competitive data transferring bandwidth within the interconnect network.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.373-377
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• 1995

Four Bacillus thuringiensis isolates obtained from soil samples in Korea produce parasporal inclusions non-toxic to 10 insect species of three orders, Lepidopera, Diptera and Coleoptera. These four isolates are named NTB-1, NTB-2, NTB-3 and NTB-4, respectively. The morphology of parasporal inclusions of four isolates observed by phase contrast- and scanning electron microscope was all ovoid. Characterization of four non-toxic B. thuringiensis isolates was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and restriction endonuclease analysis. The results showed that parasporal inclusion proteins and total plasmid DNA profiles of four isolates are different from other known non-toxic B. thuringiensis strains', suggesting that four isolates are novel.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.67-70
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• 2018

다수의 계산노드를 초고성능 상호연결망으로 연결하여 클러스터 시스템으로 구성하는 HPC에서 인터 콘넥션 기술로 Infiniband, Ethernet등의 기술이 많이 사용된다. PCIe 기반의 노드간 직접 연결 기술로는 NTB(Non-Transparent Bridge) 기반의 인터콘넥션 기술이 있으나, NTB의 기본은 두 노드간에 분리된 메모리를 공유하는 방식이다. 본 논문에서는 다중 NTB 포트에 직접 연결된 다수의 호스트들간에 무스위치 네트워크를 구성하여 NTB 통신을 이용한 데이터 공유 방법의 설계와 구현에 대해서 다룬다. 각 호스트에 연결된 두 개의 NTB포트를 이용해서 링 네트워크를 구성하고, 링 네트워크 상에서 NTB 인터컨넥션을 이용한 데이터 공유 방식의 구현을 하였다. 이와 같이 PCIe 기반 무스위치 네트워크를 통해서 Cost-Effective한 HPC 상호연결망을 구성할 수 있다.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.51-54
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• 2016

NTB는 transparent bridge와 공통적으로 독립적인 PCI bus(PCI 또는 PCI Express bus)에 대해서 데이터 전송 경로(path)를 제공한다는 점에서 기능적으로 유사하다. 그러나, NTB와 transparent bridge 간의 가장 큰 차이점은 NTB가 사용될 경우에 bridge의 하향부분(downstream side)에 위치한 장치들은 상향부분(upstream side)에서는 보이지 않는다는 점이다. 이는 bridge의 하향부분(downstream side)에 위치한 인텔리전트(intelligent)한 제어기(예를들면 CPU를 포함하는 컴퓨터)가 자신의 downstream side에 위치하는 서브시스템 내 각종 장치들을 독립적으로 관리할 수 있다는 점이다. NTB는 또한 첫 번째 호스트(primary host)의 PCI bus로 구성된 서브시스템(subsystem) 계층구조(hierarchy)에 두 번째 호스트(secondary host)를 연결하는 데 사용될 수 있다. 이는 두 시스템간 통신을 가능하도록 하는 반면, 두 시스템을 서로 격리시키는 효과도 발생한다. 즉, NTB는 일반적으로 도어벨(doorbell)을 통해서 bridge의 다른 편에 위치한 장치에 대해서 인터럽트를 보낼 수 있으며, 또한, scratchpad 레지스터를 보유하고 있어 bridge의 양측에서 데이터를 상호 공유함으로써 interprocessor communication 할 수 있다.

• Journal of Information Processing Systems
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• v.18 no.1
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• pp.159-172
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• 2022

The role of the interconnect network, which connects computing nodes to each other, is important in high-performance computing (HPC) systems. In recent years, the peripheral component interconnect express (PCIe) has become a promising interface as an interconnection network for high-performance and cost-effective HPC systems having the features of non-transparent bridge (NTB) technologies. OpenSHMEM is a programming model for distributed shared memory that supports a partitioned global address space (PGAS). Currently, little work has been done to develop the OpenSHMEM library for PCIe-interconnected HPC systems. This paper introduces a prototype implementation of the OpenSHMEM library through a switchless interconnect network using PCIe NTB to provide a PGAS programming model. In particular, multi-interrupt, multi-thread-based data transfer over the OpenSHMEM shared memory model is applied at the implementation level to reduce the latency and increase the throughput of the switchless ring network system. The implemented OpenSHMEM programming model over the PCIe NTB switchless interconnection network provides a feasible, cost-effective HPC system with a PGAS programming model.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.881-884
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• 2004

Apoptosis inducers for cancer therapy have been studied. Among hundreds of inducers, peptide anticancer drugs have many advantages such as being not harmful to humans, high selectivity, and dependence on their structures. Naltriben (NTB) is an octapeptide consisting of DPhe-Cys-Tyr-DTrp-Orn-Thr-Pen-Thr-$NH_2$. Several NTB analogues are known. In this experiment, apoptotic activities of NTB analogues with 8 amino acids were tested using flow cytometry. The conformational study of NTB was carried out using NMR spectroscopy and molecular modeling. Here, the relationships between conformations of NTB analogues and their apoptotic effects are reported.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.126-130
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• 1998

A noninsecticidal strain, Bacillus thuringiensis NTB-88, isolated from Korean soil, had a typical bipyramidal parasporal inclusion and its serotype is identical to B. thuringiensis subspmorrisoni (H8a8b). To elucidate differences between insecticidal and noninsecticidal strains, we compared strain NTB-88 to other toxic B. thuringiensis subsp. morrisoni strains (HD-12 and PG-14). Restriction endonucleases digested plasmid DNA patterns showed that strain NTB-88 was different from lepidopteran-toxic strain, HD-12, but it was similar to dipteran-toxic strain, PG-14. The gene type of strain NTB-88 was different from those of other insecticidal strains, Furthermore, the NH2-terminal amino acid sequence of crystal protein of strain NTB-88 had no relation to those of the previously known $\delta$-endotoxins in other toxic strains as well as HD-12 and PG-14 strains. Therefore, the noninsecticidal crystal protein in strain NTB-88 is novel and its property is different from insecticidal ones.

• Journal of Korean Medicine Rehabilitation
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• v.32 no.4
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• pp.9-18
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• 2022

Objectives This study was conducted to confirm the anti-inflammatory effect of Naetakbaekryeom-san (NTB), and whether it could be another treatment for inflammatory diseases. Methods The NTB water extract was extracted with hot water at 100℃ for 2 hours, concentrated at 80℃ under reduced pressure, and used. After 2 hours of pretreatment with NTB and positive control Bay11-7082, nitric oxide (NO), inducible NO synthase (iNOS), interleukin (IL)-6, IL-1𝛽, tumor necrosis factor alpha (TNF-𝛼) were measured in RAW264.7 cells activated with lipopolysaccharides (LPS) 500 ng/mL. After 2 hours of pretreatment with NTB, the anti-inflammatory effect of NTB was evaluated by measuring nuclear factor kappa-light-chain-enhancer of activated B cells (NF-𝜅B) in RAW264.7 cells and 293T cells activated with phorbol 12-myristate 13-acetic acid (PMA) 30 ng/mL. Results In RAW264.7 cells activated with LPS, NTB at concentrations of 0.1, 0.3, and 1.0 mg/mL showed no cytotoxicity, significantly inhibited NO production and inhibition of iNOS expression. TNF-𝛼 cytokine levels was not regulated, but NTB at each concentration inhibited the production of IL-1𝛽 and IL-6, and the effect was higher than that of the positive control Bay11-7082 (20 𝜇M). In PMA-activated RAW264.7 cells and 293T cells, each concentration of NBT decreased the NF-𝜅B transcriptional activity, with the greatest decrease at 1 mg/mL. Conclusions These results demonstrated the anti-inflammatory effect of NTB water extracts, but further studies such as comparison of anti-inflammatory effects and antioxidant effects by NTB component, comparison of effects according to extraction solvents, and clinical studies are needed.

• The Magazine of the IEIE
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• v.22 no.6
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• pp.83-93
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• 1995

정부에서는 다가오는 2000년대에 우리나라의 과학기술을 선진 7개국 수준으로 진입시킴은 물론 기술개발을 통한 국가 경쟁력의 확보를 목표로 여러 기술분야에 걸쳐 HAN(highly Advanced national) 프로젝트를 기획하고 1992년부터 기술개발에 착수하였다. 현재 국가 초고속 정보통신망 기반 구축사업의 일부로 추진되고 있는 HAN/BISDN 프로젝트는 통신망, 교환, 전송, 및 단말 분야로 나뉘어 초고속 정보통신망의 구축에 소요되는 다양한 장치들을 단계적으로 개발할 예정이다. 장기간에 걸쳐 여러 기관들이 다양한 장치들을 공동으로 개발하게 되는 이러한 대형 프로젝트의 경우 개발 결과물을 통신망에 적용하여 사업화하기 이전에 검증하기 위한 통신망 테스트베드(Network Testbed:NTB)의 구축과 운용이 절실히 필요하다. 본고는 이러한 NTB의 목적 및 필요성 등에 관하여 언급한 뒤 세계 여러 나라에서 구축 및 운용되는 테스트베드들의 사례를 살펴보고, HAN/BISDN 프로젝트중 NTB 구축 계획에 관하여 기술한 것이다.