• Title/Summary/Keyword: NAL

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Probabilistic free vibration analysis of Goland wing

  • Kumar, Sandeep;Onkar, Amit Kumar;Manjuprasad, M.
    • International Journal of Aerospace System Engineering
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    • v.6 no.2
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    • pp.1-10
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    • 2019
  • In this paper, the probabilistic free vibration analysis of a geometrically coupled cantilever wing with uncertain material properties is carried out using stochastic finite element (SFEM) based on first order perturbation technique. Here, both stiffness and damping of the system are considered as random parameters. The bending and torsional rigidities are assumed as spatially varying second order Gaussian random fields and represented by Karhunen Loeve (K-L) expansion. Here, the expected value, standard deviation, and probability distribution of random natural frequencies and damping ratios are computed. The results obtained from the present approach are also compared with Monte Carlo simulations (MCS). The results show that the uncertain bending rigidity has more influence on the damping ratio and frequency of modes 1 and 3 while uncertain torsional rigidity has more influence on the damping ratio and frequency of modes 2 and 3.

Photochemical Reaction of Nalidixic Acid in Methanol

  • Park, Hyoung-Ryun;Park, Ok-Hyun;Lee, Hong-Yune;Seo Jung-Ja;Bark, Ki-Min
    • Bulletin of the Korean Chemical Society
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    • v.24 no.11
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    • pp.1618-1622
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    • 2003
  • The photochemical reactions of methanolic nalidixic acid (NAL) solution in the absence and in the presence of air have been investigated using 300 nm UV light. From the reactions, 1-ethyl-7-methyl-4-oxo-4-hydro-1,8-naphthyridine (EMDN),formic acid, and formaldehyde are produced. In the presence of air, hydrogen peroxide is also detected along with the products listed above. The presence of oxygen during the irradiation of methanolic NAL solution effects on the product yield. The initial quantum yields of the products and of the NAL decomposition are determined. Possible reaction pathways for the photochemical reaction are suggested on the basis of the products analysis.

Adaptive Linear Interpolation Using the New Distance Weight and Local Patterns (새로운 거리 가중치와 지역적 패턴을 고려한 적응적 선형보간법)

  • Kim, Tae-Yang;Jeon, Yeong-Gyun;Jeong, Je-Chang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.12C
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    • pp.1184-1193
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    • 2006
  • Image interpolation has been widely used and studied in the various fields of image processing. There are many approaches of varying complexity and robustness. In this paper, a new distance weight is proposed for the conventional linear interpolation. In comparison with the conventional linear weight, the new distance weight uses a quadratic or cubic polynomial equation to reflect that the interpolated value should be influenced more by the value of closer pixels in an input image. In this paper, the new adaptive linear (NAL) interpolation, which considers patterns near the interpolated value, is also proposed. This algorithm requires a pattern weight, which is used to determine the ratio of reflection on local patterns, to obtain an interpolated image that exhibits better quality at various magnification factors (MF). In the computer simulation, not only did the NAL interpolation exhibit much lower computational complexity than conventional bicubic interpolation, it also improved peak signal-to-noise ratios (PSNR).

Control of Layered Encryption for SVC Video Streaming (SVC 비디오 스트리밍을 위한 계층적 암호화 제어 기법)

  • Hwang, Jae-Hyung;Seo, Kwang-Deok;Jung, Soon-Heung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.7
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    • pp.1617-1625
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    • 2010
  • Recently, the standardization of SVC technology which can provide adaptive video quality in diverse service environments has been completed. This paper proposes a layered encryption technique which takes into account the prioritized layer characteristics of SVC and control constant encryption complexity satisfying the target computational complexity. In particular, it analyzes the importance of NAL unit in the SVC video layer and suggests a method to apply appropriate encryption complexity proper for it. The effectiveness of the proposed method is proved through the comparison of time required for encryption and the reconstructed video quality using imperfect decryption key.

Ionization and Divalent Cation Complexation of Quinolone Antibiotics in Aqueous Solution

  • Park, Hyeong Ryun;Jeong, Gwang Yeong;Lee, Hyeong Cheol;Lee, Jin Gi;Baek, Gi Min
    • Bulletin of the Korean Chemical Society
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    • v.21 no.9
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    • pp.849-854
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    • 2000
  • The protonation and divalent cation complexation equilibria of several quinolone antibiotics such as nalidixic acid (NAL),flumequine (FLU), oxolinic acid (OXO), ofloxacin (OFL), norfloxacin (NOR) and enoxacin (ENO) have been examined by potentiome tric titration and spectrophotometric method. The antibacterial activity of these drugs depends upon the pH and the concentration of metal cations such as Mg2+ , Ca2+ in solu-tion. The apparent ionization constants of NAL, FLU, OXO, OFL, NOR and ENO in aqueous solution were found to be 6.33, 6.51, 6.72, 7.18, 7.26, and 7.53, respectively. In aqueous solution, NAL, FLU and OXO were found to be present mainly as two chemical species : molecularand anionic; but OFL, NOR and ENO were present mainly as three chemical species : anionic, neutral zwitterionic and cationic form, in equilibrium. The pKa1 and pKa2are found to be 6.10 and 8.28 for OFL; 6.23 and 8.55 for NOR; 6.32 and8.62 for ENO, respec-tively. The complex formation constants between OFL, NOR or FLU and some divalent cations are measured at pH 7.5. The 1 : 1 complexes are formed mainly by ion-dipole interaction. FLU has somewhat larger Kf values than OFL and NOR because its molecular size is small and the FLU is present asanionic form at pH 7.5.

A Study on the Performance of Companding Algorithms for Digital Hearing Aid Users (디지털 보청기 사용자를 위한 압신 알고리즘의 성능 연구)

  • Hwang, Y.S.;Han, J.H.;Ji, Y.S.;Hong, S.H.;Lee, S.M.;Kim, D.W.;Kim, In-Young;Kim, Sun-I.
    • Journal of Biomedical Engineering Research
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    • v.32 no.3
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    • pp.218-229
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    • 2011
  • Companding algorithms have been used to enhance speech recognition in noise for cochlea implant users. The efficiency of using companding for digital hearing aid users is not yet validated. The purpose of this study is to evaluate the performance of the companding for digital hearing aid users in the various hearing loss cases. Using HeLPS, a hearing loss simulator, two different sensorinerual hearing loss conditions were simulated; mild gently sloping hearing loss(HL1) and moderate to steeply sloping hearing loss(HL2). In addition, a non-linear compression was simulated to compensate for hearing loss using national acoustic laboratories-non-linear version 1(NAL-NL1) in HeLPS. In companding, the following four different companding strategies were used changing Q values(q1, q2) of pre-filter(F filter) and post filter(G filter). Firstly, five IEEE sentences which were presented with speech-shaped noise at different SNRs(0, 5, 10, 15 dB) were processed by the companding. Secondly, the processed signals were applied to HeLPS. For comparison, signals which were not processed by companding were also applied to HeLPS. For the processed signals, log-likelihood ratio(LLR) and cepstral distance(CEP) were measured for evaluation of speech quality. Also, fourteen normal hearing listeners performed speech reception threshold(SRT) test for evaluation of speech intelligibility. As a result of this study, the processed signals with the companding and NAL-NL1 have performed better than that with only NAL-NL1 in the sensorineural hearing loss conditions. Moreover, the higher ratio of Q values showed better scores in LLR and CEP. In the SRT test, the processed signals with companding(SRT = -13.33 dB SPL) showed significantly better speech perception in noise than those processed using only NAL-NL1(SRT = -11.56 dB SPL).

Genotype analysis of genes involved in increasing grain number per panicle in rice germplasm (벼 유전자원의 수당립수 증진 유전자 유전형 분석)

  • Shin, Dongjin;Kim, Tae-Heon;Lee, Ji-Yoon;Cho, Jun-Hyun;Lee, Jong-Hee;Song, You-Chun;Park, Dong-soo;Oh, Myeong-Kyu
    • Journal of Plant Biotechnology
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    • v.44 no.4
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    • pp.356-363
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    • 2017
  • ARice is an important staple food in the world and rice yield is one of the main traits for rice breeding. Several genes involved in increasing the yield have been identified through map-based gene cloning within natural variations in rice. These identified genes are good targets for introducing a genetic trait in molecular breeding. Here, we chose five genes reported to be involved in increasing grain number per panicle in rice; Gn1a, dep1, Apo1, Ghd7, and Nal1. We developed In/Del markers for Gn1a, and dep1, Apo1, and applied the reported SNP markers for Ghd7 and Nal1. We were easily able to examine the genotype of each gene on agarose gel. We tested the genotypes on 479 rice resources that we held with evaluated molecular markers. According to the genotype of each gene, rice resources were divided into 13 haplotypes, and most of the Indica and Japonica varieties were included in haplotypes 1 and 13, respectively. When we examined the effect of each gene on grain number per panicle and panicle number per plant, panicle number per plant in the yield negative allele group for each gene was reduced by approximately 0.3 to 0.8 compared to that in the yield positive allele group. However, the number of yield positive alleles for each gene was higher by about 21 to 27 grains per panicle than that of yield negative alleles. Although most of the varieties were grouped in haplotypes 1 and 13, we believe that this genotype information with evaluated molecular markers will be useful in rice breeding for increasing the yield with grain number per panicle.

A New High Efficient Bi-directional DC/DC Converter in the Dual Voltage System

  • Lee Su-Won;Lee Seong-Ryong;Jeon Chil-Hwan
    • Journal of Electrical Engineering and Technology
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    • v.1 no.3
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    • pp.343-350
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    • 2006
  • This paper introduces a new high efficient bi-directional, non-isolated DC/DC converter. Through variations of the topology of the conventional Cuk converter, an optimum bi-directional DC/DC converter is proposed. Voltage and current in the proposed DC/DC converter are continuous. Furthermore, the efficiency in both step-up and step-down mode is improved over that of the conventional bi-directional converter. To prove the validation for the proposed converter, simulations and experiments are executed with a 300W bi-directional converter.