• 제목/요약/키워드: CPE

검색결과 263건 처리시간 0.032초

충돌방지레이더의 허상방지용 전파흡수제에 관한 연구 (A Study on the EM Wave Absorber for Eliminating False Images in Collision-Avoidance Radar)

  • 최창묵;임봉택;안용운
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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    • pp.117-120
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    • 2008
  • 본 논문은 차량 충돌방지 레이더의 허상방지용 전파흡수체를 유전손실재료인 $TiO_2$을 이용하여 개발하였다. 먼저 전파흡수체 샘플을 유전손실재료인 $TiO_2$ 와 바인더인 CPE를 사용하여 조성비별 제작하고, 네트워크 아날라이저를 이용하여 측정한 5-parameter로부터 1-Port Method를 이용하여 복소비유전율을 계산하였다. 그리고 계산된 복소비유전율을 이용하여 전파흡수체를 설계 및 제작한 결과 조성비 $TiO_2$:CPE=70:30 wt.%, 두께 1.85 mm, 주파수 76-77 GHz에서 20 dB 이상의 전파를 흡수하는 전파흡수체를 개발하였다.

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함염소 폴리에틸렌의 열안정성에 관한 연구 (A Study on Thermal Stability of Chlorinated Polyethylene)

  • 설수덕;이내우
    • 한국가스학회지
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    • 제1권1호
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    • pp.120-126
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    • 1997
  • 저밀도 폴리에틸렌 (LDPE)과 $25\%{\~}48\%$의 함염소 폴리에틸렌(CPE)에 대한 열분해상태를 20ml/min의 질소기류와 $4^{\circ}C{\~}20^{\circ}C$/min의 여러 가지 가열율에서 열중량분석으로 검토하였다. 반응의 열분해 활성화에너지값을 얻기 위하여 수학적인 방법으로는 미분법(Friedman)과 적분법(Ozawa)법이 사용되었다. 위의 방법으로 평가된 활성화에너지는 각각이 잘 일치하였고, 최고평균 활성화에너지는 71.72kcal/mol로 계산되었다. LDPE와 CPE의 열분해는 주쇄분해반응이고 실제 열분해곡선은 이론식과 잘 일치하는 것으로 사료된다.

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W-대역에서 유전손실재료인 $TiO_2$의 전파흡수 특성 분석 (Analysis of EM Wave Absorption Properties in W-band using $TiO_2$)

  • 최창묵;김동일;고광섭
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2007년도 춘계종합학술대회
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    • pp.95-98
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    • 2007
  • 본 논문은 W-대역에서 유전손실 재료인 $TiO_2$의 전파흡수 특성을 분석하였다. 먼저 전파흡수체 샘플을 손실재료로 $TiO_2$ 와 바인더로 CPE를 사용하여 조성비별 제작하고, 네트워크 아날라이저를 이용하여 측정한 S-parameter로부터 $\ell-2\ell$ 법을 이용하여 재료정수를 계산하였다. 그리고 샘플들의 재료정수와 전파흡수 특성을 분석한 결과 조성비 $TiO_2:CPE=70:30wt.%$에서 우수한 전파흡수 특성을 보임을 확인하였다.

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우리별 1호에서의 SPACE RADIATION 환경 조사 (CRE ECPERIMENT OF KITSAT-1)

  • 신영훈;민경욱;최영완;김성헌
    • Journal of Astronomy and Space Sciences
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    • 제11권1호
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    • pp.131-145
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    • 1994
  • Cosmic Ray Experiment (CRE)는 KITSAT-1 의 여 러 module 중 하나로 Total D Dose Experiment (TDE) 와 Cosmic Particle Experiment (CPE) 두개의 sub-system 으로 구성되어 있다. CRE 의 목적은 KITSAT-1 궤도에서의 우주 환경을 조사하는 것이다. KITSAT-1 의 궤도는 inner Van Allen belt에 위치하며, 이 지역 에셔는 고에너지 proton들이 많이 분포하고 있어 위성체에 단기적인 또는 장기적인 radiation 효과를 미치고 있다. 1년여의 설험 결과로부터 Van Allen belt가 무척 안정되어 있고 태양의 활동이 CPE,TDE 및 SEU (Single Event Upset) rate 에 영향을 줌을 알 수 있었다. 또한 CREME code 에 의해 예상됐던 것보다 많은 고에너지 입자 flux가 관찰되었다.

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Propagation of lymphocystis disease virus (LCDV) in the FIN cell line originated from olive flounder Paralichthys olivaceus fin

  • Hossain, Mosharrof;Kim, Wi-Sik;Jung, Sung-Ju;Oh, Myung-Joo
    • 한국어병학회지
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    • 제24권2호
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    • pp.47-51
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    • 2011
  • The present study demonstrated lymphocystis disease virus (LCDV) propagation through cytopathic effects (CPE) formation and LCDV detection in olive flounder fin (FFN) cells by polymerase chain reaction (PCR) and fluorescent antibody technique (FAT) methods. Tissue filtrates from the cluster cells produced CPE in FFN cells, which initially cells became enlarged and gradually underwent fusion en masse. Infectivity of culture grown LCDV using the FFN cells reached $10^{2.3}$ $TCID_{50}$/ml at 4 days post infection and the highest titer was measured $10^{6.5}$ $TCID_{50}$/ml at 12 days. The viral DNA was detected in the cell culture supernatants showing CPE and the CPE cells by PCR. Antigen specific strong fluorescence reacting with monoclonal antibody against the virus revealed the presence of viral antigen in the cytoplasm of infected FFN cells. These results suggest that the FFN cell line originated from the olive flounder has a susceptibility of the LCDV.

Taxonomy and Phylogeny of Neosiphonia japonica (Rhodomelaceae,Rhodophyta) Based on rbcL and cpeA/B Gene Sequences

  • 김명숙;양은창
    • ALGAE
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    • 제21권3호
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    • pp.287-294
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    • 2006
  • Neosiphonia japonica is a rhodomelacean red alga that occurs in Korea, Japan, China, far-east Russia, northwest America, and New Zealand. Although it is distinguished by a bush-like habit having four pericental cells with cortication and numerous branches on axes, the taxonomy of N. japonica is still problematic. To investigate the taxonomy and phylogeny of the species, we analyzed rbcL and phycoerythrin (cpeA/B) genes from 19 samples of N. japonica and putative relatives. Phylogenetic trees from both genes show that N. japonica from Korea, Japan, New Zealand, and USA is clearly separated from N. decumbens, N. harlandii, and N. flavimarina from the Pacific Ocean. Instead, N. harveyi from the Atlantic Ocean was more related to N. flavimarina than to N. japonica. This result supports morphological and distributional differences between N. japonica and N. harveyi. However, the close relationship between these species suggests that they might have a recent most common ancestor. This is the second report to use the cpeA/B gene for evaluating species diversity in the Rhodophytes.

고분자 전해질 FC 평가용 등가회로 검토 (Investigation of Equivalent Circuit for PEMFC Assessment)

  • 명광재
    • 대한기계학회논문집B
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    • 제35권9호
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    • pp.897-902
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    • 2011
  • PEMFC 의 내부에서 발생하는 화학반응은 계면의 물리적 조건 및 물성에 지배되고 그 거동은 임피던스로 표현된다. 일반적으로 임피던스 특성은 전기적 등가회로로 표현이 가능하기 때문에 PEMFC의 임피던스 계측 결과를 등가회로를 이용하여 해석함으로써 간단히 성능 진단을 할 수 있을 것이다. 본 연구에서는 이러한 등가회로를 이용하여 고분자 전해질 연료전지의 특성평가에 관한 기초연구를 수행하였다. 교류 임피던스 계측 값과 다양한 등가회로(단순 등가회로, CPE 를 고려한 등가회로, 2 개의 시정수를 고려한 등가회로, 2 개의 CPE 를 고려한 등가회로)를 이용하여 특성평가를 수행하였다. 그 결과 등가회로를 이용한 PEMFC 의 특성평가가 가능하고, 2 개의 CPE 를 고려한 등가회로가 가장 정도가 높음을 확인하였다.

HoneyThing: A New Honeypot Design for CPE Devices

  • Erdem, Omer;Pektas, Abdurrahman;Kara, Mehmet
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권9호
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    • pp.4512-4526
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    • 2018
  • The Internet of Things (IoT) has become an emerging industry that is broadly used in many fields from industrial and agricultural manufacturing to home automation and hospitality industry. Because of the sheer number of connected devices transmitting valuable data, the IoT infrastructures have become a main target for cyber-criminals. One of the key challenges in protecting IoT devices is the lack of security measures by design. Although there are many hardware and software based security solutions (firewalls, honeypots, IPDS, anti-virus etc.) for information systems, most of these solutions cannot be applied to IoT devices because of the fact that IoT devices have limited computing resources (CPU, RAM,). In this paper, we propose a honeypot system called HoneyThing for modem/router devices (i.e. a kind of IoT device). HoneyThing emulates TR-069 protocol which is prevalent protocol used to remotely manage customer-premises equipment (CPE) devices, e.g. modems, routers. Honeything also serves an embedded web server simulating a few actual, critical vulnerabilities associated with the implementation of TR-069 protocol. To show effectiveness of the HoneyThing in capturing real world attacks, we have deployed it in the Internet. The obtained results are highly promising and facilitate to reveal network attacks targeting to CPE devices.

Highly-sensitive Detection of Salvianolic Acid B using Alumina Microfibers-modified Electrode

  • Sun, Dong;Zheng, Xiaoyong;Xie, Xiafeng;Yang, Xiaofeng;Zhang, Huajie
    • Bulletin of the Korean Chemical Society
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    • 제34권11호
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    • pp.3357-3361
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    • 2013
  • Alumina microfibers with porous structures were prepared through hydrothermal reaction, and then used to modify the surface of carbon paste electrode (CPE). After modification with alumina microfibers, the electrochemical activity of CPE was found to be greatly improved. On the surface of alumina microfibers-modified CPE, the oxidation peak current of salvianolic acid B, a main bioactive compound in Danshen with anti-oxidative and anti-inflammatory effects, was remarkably increased compared with that on the bare CPE surface. The influences of pH value, amount of alumina microfibers and accumulation time were studied. Based on the strong signal amplification effects of alumina microfibers, a novel electrochemical method was developed for the detection of salvianolic acid B. The linear range was from 5 ${\mu}gL^{-1}$ to 0.3 mg $L^{-1}$, and the detection limit was 2 ${\mu}gL^{-1}$ (2.78 nM) after 1-min accumulation. The new method was successfully used to detect salvianolic acid B in ShuangDan oral liquid samples, and the recovery was over the range from 97.4% to 102.9%.

Antiherpetic Activities of Flavonoids against Herpes Simplex Virus Type 1 (HSV-1) and Type 2 (HSV-2) In Vitro

  • Lyu Su-Yun;Rhim Jee-Young;Park Won-Bong
    • Archives of Pharmacal Research
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    • 제28권11호
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    • pp.1293-1301
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    • 2005
  • Flavonoids, a group of low molecular weight phenylbenzopyrones, have various pharmacological properties including antioxidant, anticancer, bactericidal, and anti-inflammatory. We carried out anti-herpetic assays on 18 flavonoids in five classes and a virus-induced cytopathic effect (CPE) inhibitory assay, plaque reduction assay, and yield reduction assay were performed. When flavonoids were applied at various concentrations to Vero cells infected by HSV-1 and 2, most of the f1avonoids showed inhibitory effects on virus-induced CPE. Among the flavonoids, EC, ECG (flavanols), genistein (isoflavone), naringenin (flavanone), and quercetin (flavonol) showed a high level of CPE inhibitory activity. The antiviral activity of flavonoids were also examined by a plaque reduction assay. EC, ECG, galangin, and kaempferol showed a strong antiviral activity, and catechin, EGC, EGCG, naringenin, chrysin, baicalin, fisetin, myricetin, quercetin, and genistein showed moderate inhibitory effects against HSV-1. In these experiments, flavanols and flavonols appeared to be more active than flavones. Furthermore, treatment of Vero cells with ECG and galangin (which previously showed strong antiviral activities) before virus adsorption led to a slight enhancement of inhibition as determined by a yield reduction assay, indicating that an intracellular effect may also be involved.