• Title/Summary/Keyword: selective

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Disposable Nitrate-Selective Optical Sensor Based on Fluorescent Dye

  • Kim, Gi-Young;Sudduth, Kenneth A.;Grant, Sheila A.;Kitchen, Newell R.
    • Journal of Biosystems Engineering
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    • v.37 no.3
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    • pp.209-213
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    • 2012
  • Purpose: This study was performed to develop a simple, disposable thin-film optical nitrate sensor. Methods: The sensor was fabricated by applying a nitrate-selective polymer membrane on the surface of a thin polyester film. The membrane was composed of polyvinylchloride (PVC), plasticizer, fluorescent dye, and nitrate-selective ionophore. Fluorescence intensity of the sensor increased on contact with a nitrate solution. The fluorescence response of the optical nitrate sensor was measured with a commercial fluorospectrometer. Results: The optical sensor exhibited linear response over four concentration decades. Conclusions: Nitrate ion concentrations in plant nutrient solutions can be determined by direct optical measurements without any conditioning before measurements.

An Optimal Selective Protection Scheme for Scalable Video Coding

  • Hendry, Hendry;Kim, Munchurl
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.07a
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    • pp.294-295
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    • 2011
  • The fundamental problem of selective protection scheme for encoded bitstreams is to find an efficient algorithm to select the set of frames required to be encrypted that can maximize protection effect with the minimum amount of protected data is required. In this paper, we propose an optimal selective protection scheme for SVC bitstreams by protecting the best combination of frames for selective protection in the sense that the amount of data required for protection is minimized and the resulting visual quality degradation is maximized. The selection of the frames to be encrypted is done by first expressing R-Q (protection rate - visual quality) relationship with Lagragian cost model. The experimental results show that, compared to protecting SVC bitstreams layer by layer, the proposed scheme gives superior performance in terms of protection effectiveness due to its better selection of frames for protection given protection bit budgets.

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Stydies on the Selective Screening Method of Bifidobacteria Used in Yoghurt (호상 요구르트 제품에 이용되는 Bifidobacteria 의 선택적 검출 방법)

  • 박희경;허태련
    • Microbiology and Biotechnology Letters
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    • v.23 no.2
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    • pp.214-219
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    • 1995
  • In fermentation of dairy products, bifidobacteria is used in conjunction with other lactic acid bacteria, such as L. acidophilus, L. bulgaricus and S. thermophilus, rendering the enumeration of bifidobacteria difficult. In order to develop optimum conditions for selective enumeration of bifidobacteria, we examined MIC of several antibiotics against various bifidobacteria and other lactic acid bacteria. The growth of L. acidophilus, L. bulgaricus and S. thermophilus were inhibited by lithium chloride at the concentration of less than 4 mg/ml, whereas growth inhibition of bifidobacteria occurred at concentrations over 6-10 mg/ml. Tetracycline and chloramphenicol were also found to selectively inhibit growth of other lactic acid bacteria at the concentration of 1-3 $\mu$g/ml. Addition of 6 mg/ml lithium chloride, 1 $\mu$g/ml, tetracycline or 3 $\mu$g/ml chloramphenicol to medium was found to be optimal for selective enumeration of bifidobacteria. By using these three inhibitory chemicals in the TPY medium, higher number of bifidobacteria were selectively isolated than with NPNL agar and LP agar.

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On the Performance of Turbo Codes-Based Hybrid ARQ with Segment Selective Repeat in WCDMA

  • Shi Tao;Cao Lei
    • Journal of Communications and Networks
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    • v.8 no.2
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    • pp.212-219
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    • 2006
  • In this paper, a new turbo codes-based hybrid automatic repeat request (TC-HARQ) scheme with segment selective repeat (SSR) is proposed. The main strategy is, upon retransmission, to repeat the data that are most important for the next round of decoding based on the distribution of residual errors after current decoding. The performance in terms of reliability and throughput is analyzed. To adapt to correlated fading channels where an inter-leaver is always employed before transmission, we further modify the SSR strategy so that data having experienced correlated deep fading are selected for retransmission. Finally, this proposed scheme is applied to the wideband code division multiple access (WCDMA) system under frequency selective fading channels. Simulation results demonstrate that in all single and multiple user cases, SSR-based TC-HARQ leads to significant throughput improvement with similar bit error rate (BER) performance as compared to type-I TC-HARQ.

Synthesis and Antiinflammatory Activity of 1.5- and 4.5-Disubstituted Imidazoles

  • Tuyen, Truong-Ngoc;Sin, Kwan-Seog;Kim, Hyun-Pyo;Park, Hae-Il
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.347.4-348
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    • 2002
  • Recently it has been demonstrated that selective cyclooxygenase-2 (COX-2) inhibitors retain the antiinflammatory effect but with markedly reduced GI toxicity compared to non selective inhibitors such as traditional NSAIDs. As a consequence, intense efforts have been made to develop selective COX-2 inhibtors during the last decade. Two compounds in this class. celecoxib and rofecoxib. are already in the market and are proved as potent and selective COX-2 inhibitors with much better gastric tolerance. However. there are still strong domands for a COX-2 inhibitor with improved efficacy and safety profiles. Here we report the synthesis and biological profiles of 1.5- and 4.5-disubstituted imidazole analogues as structural equivalents of cefecoxib and refecoxib. The imidazole analogues are overlapped well whth the 3D srructures of celecoxib and rofecoxib.

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Study on Selective Media for Isolation of Entomopathogenic Fungi

  • Shin, Tae-Young;Choi, Jae-Bang;Bae, Sung-Min;Koo, Hyun-Na;Woo, Soo-Dong
    • International Journal of Industrial Entomology and Biomaterials
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    • v.20 no.1
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    • pp.7-12
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    • 2010
  • To determine the optimal isolation conditions of the entomopathogenic fungi from soil, we compared their growth characteristics with non-entomopathogenic fungi on agar media containing various concentrations of cooper (II) chloride ($CuCl_2$) or dodine. The result showed that dodine medium is more selective, and the optimal concentration of dodine is determined with $50{\mu}g$/ml. We could isolate several putative entomopathogenic fungi from soil using this, and identify them using ITS analysis. As a result, 64% fungi were identified as typical entomopathogenic fungi. This selective medium may be useful to the rapid and simple isolation of entomopathogenic fungi from soil.

Control Method for the number of check-point nodes in detection scheme for selective forwarding attacks (선택적 전달 공격 탐지 기법에서의 감시 노드 수 제어기법)

  • Lee, Sang-Jin;Cho, Tae-Ho
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.387-390
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    • 2009
  • Wireless Sensor Network (WSN) can easily compromised from attackers because it has the limited resource and deployed in exposed environments. When the sensitive packets are occurred such as enemy's movement or fire alarm, attackers can selectively drop them using a compromised node. It brings the isolation between the basestation and the sensor fields. To detect selective forwarding attack, Xiao, Yu and Gao proposed checkpoint-based multi-hop acknowledgement scheme (CHEMAS). The check-point nodes are used to detect the area which generating selective forwarding attacks. However, CHEMAS has static probability of selecting check-point nodes. It cannot achieve the flexibility to coordinate between the detection ability and the energy consumption. In this paper, we propose the control method for the number fo check-point nodes. Through the control method, we can achieve the flexibility which can provide the sufficient detection ability while conserving the energy consumption.

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A Study of I-V characteristics for elevated source/drain structure MOSFET use of silicon selective epitaxial growth (Silicon Selective Epitaxial Growth를 이용한 Elevated Source/Drain의 높이가 MOSFET의 전류-전압 특성에 미치는 영향 연구)

  • Lee, Ki-Am;Kim, Young-Shin;Pak, Jung-Ho
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1357-1359
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    • 2001
  • 0.2${\mu}m$ 이하의 최소 선폭을 가지는 소자를 구현할 때 drain induced barrier lowering (DIBL)이나 hot electron effect와 같은 short channel effect (SCE)가 나타나며 이로 인하여 소자의 신뢰성이 악화되기도 한다. 이를 개선하기 위한 방법 중 하나가 silicon selective epitaxial growth (SEG)를 이용한 elevated source/drain (ESD) 구조이다. 본 연 구에서는 silicon selective epitaxial growth를 이용하여 elevated source/drain 구조를 갖는 MOSFET 소자와 일반적인 MOSFET 구조를 갖는 소자와의 차이를 elevated source/drain의 높이 변화에 따른 전류 전압 특성을 이용하여 비교, 분석하였으며 그 결과 elevated source/drain 구조가 short channel effect를 감소시킴을 확인할 수 있었다.

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A new IGBT structure for suppression of latch up with selective N+ buffer layer (Selective N+ 버퍼층을 갖는 latch up 억제를 위한 새로운 IGBT 구조)

  • Kim, Doo-Young;Lee, Byeong-Hoon;Choi, Yearn-Ik;Han, Min-Koo
    • Proceedings of the KIEE Conference
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    • 1993.11a
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    • pp.240-242
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    • 1993
  • A novel structure, which can suppress latch-up phenomena, is proposed and verified by the PISCESIIB simulation. It is shown that this structure employing the selective N+ buffer layer increases latch-up current density due to suppression of the current flowing through the p-body. The width of the N+ buffer layer is optimized considering the trade-off between the latch-up current density and the forward voltage drop. The selective buffer layer results in an improved trade-off relationship compared with the uniform buffer layer.

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Dual-Band Double-Cylindrical-Ring 3D Frequency Selective Surface

  • Can, Sultan;Karakaya, Emrullah;Bagci, Fulya;Yilmaz, Asim Egemen;Akaoglu, Baris
    • ETRI Journal
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    • v.39 no.1
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    • pp.69-75
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    • 2017
  • This study presents a dual-band 3D frequency selective surface that provides a large degree of freedom in frequency and bandwidth adjustability. The proposed structure is evaluated in terms of its structural parameters, and prototypes are fabricated. The radius of the copper rings and the height of the cylinders are considered, and are shown through full-wave electromagnetic simulations to have a significant effect on the frequency characteristics of the frequency selective surface. The measurement results of the fabricated samples are compared with the simulation results, and a satisfactory agreement is obtained.