• 미생물학회지
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• 제24권3호
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• pp.228-235
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• 1986

Zymomonas mobilis의 spheroplast 형성과 새생조건의 새량과 초|소배시에서의 새생에 대해서 연구하였다. Tris-maleate buffer (pH 5~6), $Ca^{++}$ ions 그러고 EDTA등은 out야 membrane의 투과성 변화를 야기시 켰다 Zymommonas의 세포벽은 lysozyme, mutanolysin같은 세포벽 분해효소에 의해 분해가 되지 않은 것처럼 보였고 sphe-roplast 생성에 glycine 처리는 필수적이었다. 그러나 lysozyme 처리에 의해서 spheroplast 형성이 촉진되는 것을 확인하였다. 따라서 ly sozyme과 glycine을 함께 처리함으로서 spheroplasting배지에서의 처리시간을 4시간으로 단축 할 수 있었고 재생율이 7-10% 증가되었다.

• 한국통신학회논문지
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• 제29권4C호
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• pp.550-558
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• 2004

본 연구에서는 네트워크 기반 서비스 거부 공격에 대응하여 허용된 서비스 거부확률을 보장할 수 있는 적합한 네트워크 노드를 설계하기 위해, 보호 대상 시스템 상위 노드 단의 상위 준위와 하위 준위의 물리적인 전송 대역, 버퍼 용량, 네트워크 기반 서비스 거부 공격에 소모된 자원, 허웅 가능한 공격 소스 수 및 손실 확률에 대한 관계를 분석한 제한 조건을 도출하였고 이에 대한 네트워크 노드의 자원과 비용의 관계를 분석하여 보장된 가용성을 유지할 수 있는 경제적 노드의 자원 구성을 설계하였다. 따라서 본 연구 결과는 네트워크 기반 서비스 거부 공격에 대응할 수 있는 효율적인 보안 네트워크 구조 설계에 기여할 것으로 기대된다.

• ETRI Journal
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• 제37권3호
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• pp.491-501
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• 2015

Spectrum sensing is an elementary function in cognitive radio designed to monitor the existence of a primary user (PU). To achieve a high rate of detection, most techniques rely on knowledge of prior spectrum patterns, with a trade-off between high computational complexity and long sensing time. On the other hand, blind techniques ignore pattern matching processes to reduce processing time, but their accuracy degrades greatly at low signal-to-noise ratios. To achieve both a high rate of detection and short sensing time, we propose fast spectrum sensing with coordinate system (FSC) - a novel technique that decomposes a spectrum with high complexity into a new coordinate system of salient features and that uses these features in its PU detection process. Not only is the space of a buffer that is used to store information about a PU reduced, but also the sensing process is fast. The performance of FSC is evaluated according to its accuracy and sensing time against six other well-known conventional techniques through a wireless microphone signal based on the IEEE 802.22 standard. FSC gives the best performance overall.

• KIEAE Journal
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• 제7권5호
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• pp.87-92
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• 2007

As expansion of balconies at apartments has been legalized, the major function of the balconies as a thermal buffer zone is disappearing. This weakens the ability of window to insulate heat and multiplies surface condensation. Thus more and more residents require solutions to increasing surface condensation and aggravation in thermal comfort. This study intends to provide basic data by evaluating performance of triple layered Low-E windows, triple layered clear windows, double layered Low-E windows and double layered clear window used for expanded balconies and marketed within the country in terms of surface condensation and thermal environment through simulation. Results revealed that no surface condensation occurred at double layered Low-E windows and triple layered Low-E windows. Surface condensation took place at double layered clear windows and triple layered clear windows at a relative humidity of 60%. Thermal environment analysis suggested that double layered clear windows showed the most time falling into the range of comfort at $23^{\circ}C$. The figure were $22^{\circ}C$ for triple layered clear windows, $22^{\circ}C$ for double layered Low-E windows and $21^{\circ}C$ for triple layered Low-E windows.

• Nuclear Engineering and Technology
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• 제9권1호
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• pp.1-6
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• 1977

간장 질환 진단용 방사성 의약품인 $^{131}$ I 표지 1 요오드화 브로모프탈레인(MIBSP-$^{131}$ I)을 PH 5.3의 인삼염 완충용액에서 MIBSP와 $^{131}$ I$_2$의 동위원소 교환반응으로 제조할수 있음을 제시하였다. 비방사성 MIBSP는 브로모썰포프탈레인(BSP)을 IC1로 요오드화하고 나서 쎄파덱스 LH-20 크로마토그래피로 분리하여 얻었다. MIBSP와 $^{131}$ I의 동위원소 교환반응은 매우 빨리 일어나 10$0^{\circ}C$에서 5분안에 대략 95%의 표지수율을 보였다. 순수한 최종생성물 MIBSP-$^{131}$ I는 미량의 $H_2O$$_2$ 존재하에 약 5분간 더 반응시킨 후 PH를 조절하고 무균여과함으로써 간단히 얻어졌다.

• Bulletin of the Korean Chemical Society
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• 제21권5호
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• pp.483-486
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• 2000

A method is described for the fluorimetric determination of nickel, based on the formation of $Ni(II)-\alpha-(2-Benzimidazolyl)-\alpha'$, $\alpha''$ -(N-5-Nitro-2-Pyridylhydrazone)-toluene complex in the presence of a non-ionic surfactant. The complex has practically no fluorescence in the absence of surfactant, but the addition of Triton X-100 makes possible the fluorimetric determination of low concentrations of Ni(II) as it enhances the fluorescenceintensity of the complex by up to about 5-fold. This method is very sensitive and selectrive for the direct determination of nickel ion. The optimum conditions are a Triton X-100 concentration of 2.0 mL(5.0%, v/v) and pH $9.0\pm0.2(ammonium$ chloride-ammonia buffer). The fluorescence is measured at 337 nm of emission wavelength under 300 nm of excitation wavelength. The fluorescence intensity is a linear function of the concentration of Ni(II) in the range 5-70 ng/mL, and the detection limit is 2.0 nm/mL. The proposed method has been successfully applied to the determination of trace amounts of Ni(II) in food and human hair samples.

• Bulletin of the Korean Chemical Society
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• 제14권4호
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• pp.515-519
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• 1993

The retention behavior of proteins was investigated by using hydrophobic interaction chromatography (HIC), comparing to the results obtained in reversed-phase chromatography (RPC) described in the previous paper. A SynChropak propyl column was employed with 0.05 M phosphate buffer (pH 7.0) containing sodium sulfate. Conformational changes were recognized by examining Z values as a function of sodium sulfate concentration over a range of temperature between 5 and 65$^{\circ}C$. Z values did not change significantly at the range of the temperature showing the consistent ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ values. The sign and the magnitude of ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ of proteins in HIC were compared with those obtained in RPC. The signs of ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ of proteins in HIC were all positive, while those of proteins in RPC were all negative. These results suggested that the retention of proteins in HIC and in RPC were entropy-driven and enthalpy-driven process, respectively. From the two different investigations, it was concluded that the retention mechanism of RPC and HIC was based on the same fundamental principle in which separation is dependent on hydrophobicity, but the retention behavior of the proteins in HIC is clearly different from that observed in RPC.

• 산업경영시스템학회지
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• 제29권4호
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• pp.100-106
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• 2006

We analyze a voice/data integrated traffic model of the cellular mobile communication system with hybrid guard channels for voice and handoff calls. In a multi-service integrated wireless environment, quality of service guarantee is crucial for smooth transportation of real time information. Real time voice traffic requires a guaranteed upper bounded on both delay and packet error rate, whereas data traffic does not. Voice traffic has high transmission priority over data packets. Thus one of the important problems is the design of admission control schemes which can efficiently accommodate the differential quality of service requirements. In this paper, a hybrid guard channel scheme is considered in which arriving calls are assigned channels as long as the number of busy channels in the cell is below a predetermined first threshold. When the number of busy channels reaches the first threshold, new originating data calls are queued in the infinite data buffer. Then reaches second threshold, only handoff calls are assigned the remaining channels and new originating voice calls are blocked. We evaluate the system by a two-dimensional Markov chain approach and generating function method and obtain performance measures included blocking probability and forced termination probability.

• 대한의사협회지
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• 제61권12호
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• pp.732-739
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• 2018

The frontal sinus is a functionally important structure. It serves as a cushioning buffer to protect the brain in cases of facial trauma. Fractures of the frontal sinus can lead to aesthetic problems by causing a visible depression in the center of the forehead. The goals of frontal sinus fracture treatment have been to protect intracranial structures and to prevent early and late complications, even with invasive methods. Recently, however, the goals have shifted to preservation of nasofrontal outflow tract function through close observation and the utilization of endoscopic procedures. Excellent cosmetic results can be achieved through minimally invasive surgery. This shift in goals took place due to the ease of diagnosis and treatment of early and late complications. Therefore, patients with a frontal sinus fracture should be followed up continuously to ensure that complications are detected promptly. Herein, the authors describe the methods and current trends of frontal sinus fracture treatment.

• 정보보호학회논문지
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• 제19권2호
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• pp.75-82
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• 2009

본 논문에서는 전세계적으로 90%이상의 사용자층을 보유하고 있는 윈도우즈 OS의 API에 대한 보안 테스팅 중 Fuzz Testing을 적용하여 그 안전성을 검증하였다. 본 논문에서는 윈도우즈의 시스템 폴더 내에 구현된 함수들을 대상으로 테스팅하기 위해 Fuzz Testing 기반 자동화 방법론인 AWAFT를 제안하였다. AWAFT는 보안 취약점 중 버퍼오버플로우와 함수 파라미터 파싱 오류에 초점을 맞추고 있다. AWAFT를 자동화하기 위한 도구를 구현하였으며 Windows XP SP2 시스템 폴더에 적용한 결과 177개의 프로그램 종료 에러를 발견하였으며, 이 중 10개는 프로그램의 실행 흐름을 변경시킬 수 있는 보안상 위험한 취약점이었다. AWAFT는 윈도우즈 기반으로 개발되는 소프트웨어의 라이브러리에 대해 보안 향상을 위해 적용 가능하다.