• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1800-1808
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• 2013

Dual-responsive amphiphilic block copolymers were synthesized by combining enzymatic ring-opening polymerization (eROP) of ${\varepsilon}$-caprolactone (CL) and ATRP of N,N-dimethylamino-2-ethyl methacrylate (DMAEMA). The obtained block copolymers were characterized by gel permeation chromatography (GPC), $^1H$ NMR and FTIR-IR. The critical micelle concentration (CMC) of copolymer was determined by fluorescence spectra, it can be found that with hydrophilic block (PDMAEMA) increasing, CMC value of the polymer sample increased accordingly, and the CMC value was 0.012 mg/mL, 0.025 mg/mL and 0.037 mg/mL for $PCL_{50}$-b-$PDMAEMA_{68}$, $PCL_{50}$-b-$PDMAEMA_{89}$, $PCL_{50}$-b-$PDMAEMA_{112}$, $PCL_{50}$-b-$PDMAEMA_{89}$ was chosen as drug carrier to study in vitro release profile of anti-cancer drug (taxol). The temperature and pH dependence of the values of hydrodynamic diameter (Dh) of micelles, and self-assembly of the resulting block copolymers in water were evaluated by dynamic light scattering (DLS). The result showed that with the temperature increasing and pH decreasing, the Dh decreased. Drug-loaded nanoparticles were fabricated using paclitaxel as model. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) had been explored to study the morphology of the hollow micelles and the nanoparticles, revealing well-dispersed spheres with the average diameters both around 80 nm. In vitro release kinetics of paclitaxel from the nanoparticles was also investigated in different conditions (pH and temperature, etc.), revealing that the drug release was triggered by temperature changes upon the lower critical solution temperature (LCST) at pH 7.4, and at $37^{\circ}C$ by an increase of pH.

• Korea Information Processing Society Review
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• v.16 no.3
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• pp.18-24
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• 2009

• 한국전기화학회:학술대회논문집
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• 2003.04a
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• pp.12-12
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• 2003

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.999-1006
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• 2004

The selective media including NPC agar, DHL agar, MacConkey agar, and Cetrimide desoxycholate agar were compared to determine selectivity for the growth of bacteria Cetrimide desoxycholate agar was better than NPC agar, DHL agar, and MacConkey agar for the growth of psychrotrophic grarn-negatve bacteria including Pseudomonas. and for the inhibition of gram positive bacteria The specificity of resazurin reduction time test was investigated to determine post-pasteurization contamination of market milk. Equal volume of Cetrimide desoxycholate broth was added to market milk, which was then incubated at $21^{\circ}C$ for 18 hours. The growth of bacteria in the incubated milk was detected in resazurin reduction time test. The results in resazurin reduction time test and total bacteria number count of market milk after storage at $7^{\circ}C$ were relatively correlated each other. Pseudomonas was isolated most frequently from the market milk stored at $7^{\circ}C$ for 10 days, and Acinetobacter and Aeromonas followed. Acinetobacter, Pseudomonas and Enterobacter were frequently isolated from the mixture of market milk and Cetrimide desoxycholate broth incubated at $21^{\circ}C$ for 18hours in resazurin reduction time test.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06d
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• pp.318-321
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• 2008

현재의 소프트웨어 개발은 구현 중심의 개발에서 설계 중심의 개발로 바뀌고 있다. 설계 중심의 개발은 구현 프로그램의 시스템 개발 시간을 크게 단축할 수 있고, 정형화된 명세를 검증함으로써 설계와 구현의 일관성을 유지할 수 있으며 유지 보수가 효율적이다. 이러한 설계 중심의 개발에 있어서 SDL(Specification and Description Language)은 표준으로 재정된 기술을 구현하는데 있어 어떠한 기준 명세라 할 수 있다. 하지만 이러한 SDL도 대다수의 사람이 쉽게 알아보기에는 어려움이 있기 때문에 좀 더 높은 범용성을 위해 본 논문에서는 엔지니어들이 보편적으로 많이 사용하는 언어인 c언어를 이용해 SDL을 직접적으로 구현 해 보았는데 점점 더 발전해가는 Wireless LAN의 표준인 IEEE 802.11의 spec에 명시되어 있는 SDL을 기반으로 MAC 부분을 구현하였다.

• Proceedings of the Korea Contents Association Conference
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• 2013.05a
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• pp.245-246
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• 2013

본 논문에서는 UC/OS 시스템을 사용하는 IEEE802.11 무선 MAC프로토콜의 처리과정중탐색, 인증, 결합 과정을 이더넷으로 동작하는 하드웨어 위에 에뮬레이션하였다. 에뮬레이션 환경은ADSv1.2을 사용하고, RTOS는UC / OS를, 사용언어는 C언어를 활용하였다. 검증과정으로는 이더넷으로 구동되는AP와 단말 하드웨어에 각각PC를 하이퍼 터미널으로 접속하여 탐색, 인증, 결합과정에 해당하는 절차를 수행하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.34-43
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• 2007

In the IEEE 802.15.3 Medium Access Control (MAC) protocol, Simultaneously Operating Piconets (SOPs) are linked by the parent/child (P/C) or parent/neighbor (P/N) configuration, which work on a Time Division Multiple Access (TDMA) basis. This provides interference mitigation but the overall throughput is limited because the SOPs share the channel time exclusively. The protocol is not efficient for SOPs if we focus on the combination of interference mitigation and high throughput maintenance. In this paper Public Channel Time Allocation (Public CTA) is proposed, which is able to greatly reduce the inter-piconet interference (IPI) and achieve greater throughput without much loss of link success probability (LSP) in the SOPs. The simulation results based on the SOPs of Direct Sequence Ultra Wideband (DS-UWB) system demonstrate that the proposed scheme effectively supports the coexistence of SOPs, and it can not only significantly improve the overall throughput of SOPs but also maintain high LSP.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.225-233
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• 1997

A murine leukemia x LM fibroblast hybrid cell line with immune augmenting properties stimulated resistance to Mycobacterium avium complex (MAC) in mouse peritoneal macrophages, and in immune deficient beige mice (C57BL/6/bgj/bgj). The proliferation of MAC in mouse peritoneal macrophages was inhibited by medium conditioned by the growth of the hybrid cells (hybrid cell-CM). Under similar circumstances, media conditioned by the growth of LM cells (LM cell-CM), a mouse fibroblast cell line used as one parent in forming the hybrid cell, was exhibited no inhibitory effect. Treatment of mouse peritoneal macrophages with hybrid cell-CM, but not with LM cell-CM, stimulated the expression of each of four previously described macrophage activation antigens, suggesting that the hybrid cells formed immunomodulators in addition to those formed by LM cells. Furthermore, the morphology of the macrophages following treatment with hybrid cell-CM was clearly distinguishable from that following exposure of the cells to LM cell-CM. The therapeutic effects of hybrid cells on the progression of MAC-infection were indicated by the prolonged survival of MAC-infected immune-deficient beige mice. One hundred percent of treated animals survived more than 60 days, while untreated animals died in approximately 22 days.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.4
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• pp.91-96
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• 2004

In this paper, we introduce two forgery attacks on the PMAC. If it has no truncation then the attack requires about $2^{n}$ 2+1/ chosen texts, otherwise, the attack requires about $2^{n}$ 2+1/ chosen texts and $2^{n-}$$\tau$ MAC verifications where $\tau$ is the size of the MAC. We also give a forgery attack on the TMAC variant which requires about $2^{n}$ 2+1/ texts.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.159-164
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• 2016

This paper proposes an improved superframe structure with one : N situation of the network as a target for efficiency battery and communication performance used in the existing standard IEEE 702.15.4 MAC layer. The proposed superframe transforms and adds a two structures. First, we add the proposed scheduling interval after the arrival of the beacon. Second, we change to a structure in which one of the contention access period is divided into two. The contention access period and the contention-free access period of active portion are divided according to the LQI value of the device. Through this system-level simulation written by $c{^+^+}$, as a results show that the battery consumption and transmission performance has been increased.