• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.7
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• pp.399-406
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• 2000

We propose an nonlinear demodulation algorithm for undersampled multicomponent AM(Amplitude Modulation), FM(Frequency Modulation) and AM-FM signals. First, we derive respectively undersampling frequency of the AM, FM and AM-FM using undersampling scheme, and separate respectively monocomponent signals from multicomponent signals using periodic algebraic separation algorithm. In this case augmented separation matrix is very regular and sparse, it has a special structure. The proposed demodulation algorithm detects respectively message signals of the IA(Instantaneous Amplitude) and IF(Instantaneous Frequency) from descrete monocomponent AM, FM and AM-FM signals with an undersampling frequency to be controllable. Verifying the RMS(Root Mean Squares) errors of the detected signals, we show that the performance is excellent.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.533-538
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• 1998

추출제 Cyanex 301에 대한 NaN $O_3$ 매질에서 Am과 Eu의 추출 및 상호분리 거동에 대해 고찰하였다. Cyanex 301에 대한 Am과 Eu의 추출거동은 매우 유사하여 상호 분리할 수 없었으나 Cyanex 301을 8M NaOH로 비누화 처리하여 NaN $O_3$ 용액 매질에서 Eu에 대한 미량의 Am의 분배계수를 측정한 결과 Am에 대한 선택적 추출성이 높게 나타났다. Cyanex 301의 비누화을, 수용상의 pH 및 Eu 농도가 높아질수록 Am과 Eu의 상호 분리계수인 S $F_{AM}$Eu/는 930까지 증가되었으나 Cyanex 301에 옥탄올을 첨가할 경우에는 S $F_{Am}$ Eu/는 32.3까지 감소하였으며, Am과 Eu의 추출에 미치는 NaN $O_3$ 농도 영향은 없는 것으로 나타났다. Cyanex 301에 추출된 Am과 Eu은 pH가 4인 lM NaN $O_3$ 용액으로는 97.7% 그리고 0.05M DTPA/1.5M Lactic acid에 의해서 99% 이상 역추출되었다.

• Nuclear Engineering and Technology
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• v.14 no.4
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• pp.172-177
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• 1982

The state of Am in the concentration of 10$^{-5}$M has been studied in the pH range of 5 to 10 by filtration and centrifugation method. By the experiments, we could estimate possible Am hydrolysis products and solubility constants. If the solubility of Am (OH)$_3$ estimated by Baes and Mesmer is increased about a factor of 10, i.e. changing logk=-l8.7 to logk=-17 5 it was found that the calculated curve of Am concentration versus pH agreed completely with experimental values.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.5
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• pp.643-649
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• 1999

In this paper, we proposed that ｉ) noise-tolerant four kinds of AM(Amplitude Modulation)-FM(Frequency Modulation) demodulators are designed, ⅱ) we derived undersampling frequency through the product via energy operator of the monocomponent AM-FM signals separated form two-component AM-FM signals, and ⅲ) these four kinds of AM-FM demodulators detect respectively information signals of the IA(Instantaneous Amplitude) and IF(Instantaneous Frequency) by undersampling frequency to be different each other from the undersampled monocomponet AM-FM signals. Particularly, the proposed algorithm can control undersampling frequency by an integer factor. And these efficient AM-FM demodulators are well worked with the undersampled AM-FM signals.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.397-410
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• 2018

When considering the long-term safety assessment of spent-nuclear fuel management, americium is one of the most radio-toxic actinides. Although spectroscopic methods are widely used for the study of actinide chemistry, application of those methods to americium chemistry has been limited. Herein, we purified $^{241}Am$ to obtain a highly pure stock solution required for spectroscopic studies. Quantitative and qualitative analyses of purified $^{241}Am$ were carried out using liquid scintillation counting, and gamma and alpha radiation spectrometry. Highly sensitive absorption spectrometry coupled with a liquid waveguide capillary cell and time-resolved laser fluorescence spectroscopy were employed for the study of Am(III) hydrolysis and oxalate (Ox) complexation. $Am^{3+}$ ions under acidic conditions exhibit maximum absorbance at 503 nm, with a molar absorption coefficient of $424{\pm}8cm^{-1}{\cdot}M^{-1}$. $Am(OH)_3(s)$ colloidal particles formed under near neutral pH conditions were identified by monitoring the absorbance at around 506-507 nm. The formation of ${Am(Ox)_3}^{3-}$ was detected by red-shifts of the absorption and luminescence spectra of 4 and 5 nm, respectively. In addition, considerable enhancements of the luminescence intensities were observed. The luminescence lifetime of ${Am(Ox)_3}^{3-}$ increased from 23 to 56 ns, which indicates that approximately six water molecules are replaced by carboxylate ligands in the inner-sphere of the Am(III). These results suggest that ${Am(Ox)_3}^{3-}$ is formed through the bidentate coordination of the oxalate ligands.

• Journal of the Korean Institute of Telematics and Electronics
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• v.13 no.5
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• pp.24-29
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• 1976

In the phase locked AM signal detection, phase locked loop is used to extract a synchronous carrier from an input AM signal. Under the assumption that input noise is white Gaussian and free-running frequency of voltage controlled oscillator is the same that of an input carrier, operational behaviours of phase locked loop is analyzed and signal to noise ratio of the detection is derived quentitatively. The results show that the phase locked AM signal detection method offers a higher degree of noise mmunity than conventional AM signal detections.

• Journal of Powder Materials
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• v.24 no.6
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• pp.494-507
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• 2017

A three-dimensional physical part can be fabricated from a three-dimensional digital model in a layer-wise manner via additive manufacturing (AM) technology, which is different from the conventional subtractive manufacturing technology. Numerous studies have been conducted to take advantage of the AM opportunities to penetrate bespoke custom product markets, functional engineering part markets, volatile low-volume markets, and spare part markets. Nevertheless, materials issues, machines issues, product issues, and qualification/certification issues still prevent the AM technology from being extensively adopted in industries. The present study briefly reviews the standard classification, technological structures, industrial applications, technological advances, and qualification/certification activities of the AM technology. The economics, productivity, quality, and reliability of the AM technology should be further improved to pass through the technology adoption lifecycle of innovation technology. The AM technology is continuously evolving through the introduction of PM materials, hybridization of AM and conventional manufacturing technologies, adoption of process diagnostics and control systems, and enhanced standardization of the whole lifecycle qualification and certification methodology.

• Environmental Engineering Research
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• v.24 no.2
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• pp.309-317
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• 2019

This study evaluated the kinetics of acrylamide (AM) biodegradation by mixed culture bacteria and Enterobacter aerogenes (E. aerogenes) in sequencing batch reactor (SBR) systems with AQUASIM and linear regression. The zero-order, first-order, and Monod kinetic models were used to evaluate the kinetic parameters of both autotrophic and heterotrophic nitrifications and both AM and chemical oxygen demand (COD) removals at different AM concentrations of 100, 200, 300, and 400 mg AM/L. The results revealed that both autotrophic and heterotrophic nitrifications and both AM and COD removals followed the Monod kinetics. High AM loadings resulted in the transformation of Monod kinetics to the first-order reaction for AM and COD removals as the results of the compositions of mixed substrates and the inhibition of the free ammonia nitrogen (FAN). The kinetic parameters indicated that E. aerogenes degraded AM and COD at higher rates than mixed culture bacteria. The FAN from the AM biodegradation increased both heterotrophic and autotrophic nitrification rates at the AM concentrations of 100-300 mg AM/L. At higher AM concentrations, the FAN accumulated in the SBR system inhibited the autotrophic nitrification of mixed culture bacteria. The accumulation of intracellular polyphosphate caused the heterotrophic nitrification of E. aerogenes to follow the first-order approximation.

• Journal of fish pathology
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• v.9 no.2
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• pp.195-201
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• 1996

Ninety-six isolates of Edwardsiella tarda recovered from outbreaks of Edwardsiellosis in cultured eels(Anguilla japonica) in Kunsan, were examined for drug susceptibility, distribution and transferabilities of R plasmid. All of the E. tarda isolates examined were sensitive to gentamicin(GM), streptomycin(SM), norfloxacin(NF), and amikacin(AK). But most isolates were resistant to sulfadimethoxine(SD, 86 strains), ampicillin(AM, 84 strains), penicillin G(PM, 80 strains), nalidixic acid (NA, 67 strains), oxytetracycline(OT, 44 strains), and oxolinic acid(OA, 37 strains). Twenty different combinations of drug resistance patterns were observed : the frequently encountered pattern was SD-AM-PM-NA-OA(16 strains), SD-AM-PM-NA(14 strains), SD-AM-PM-NA-OT-OA(12 strains), SD-AM-PM-OT(10 strains), and SD-AM-PM-NA-OT(8 strains). Transferable R plasmids were found out to be carried in 78 out of 94 resistant strains, indicating that these isolates carry conjugally transferable R plasmids associated with single or multiple drugs. The frequently observed transferarble R plasmids were AM(8 strains), AM-PM-NA(8 strains), Am-SD(6 strains), PM(6 strains), and SD(6 strains) These results suggest that high dose of various antibacterials might have already been introduced to eel culture system leading to the acquirement of multi-drug resistance to wide range of antibacterials.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.237-244
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• 2004

This study was conducted to investigate the effects of dietary Animunin Powder$^{?}$ on the egg quality characteristics, blood components and nutrient digestibility in laying hens. A total of two hundred seventy laying hens were randomly allocated into three treaments with fifteen replications for eight weeks. Dietary treaments included 1) Control (CON), 2) Control + $0.1\%$ Animunin Powder$^{?}$ (AM1), 3) Control + $0.2\%$ Animunin Powder$^{?}$ (AM2). During the period of 0~4weeks, the birds fed the AM1 diet had an improved egg production compared to the birds fed the CON (P<0.05). During the period of 4~8weeks the birds fed AM1 diet showed a statistically improved egg production compared to the CON (P<0.05). However, no significant differences were founded in the egg weight. During the period of $4\~8$ weeks the hens fed the AM2 diet had improved egg yolk color compared to the hens fed CON and AM1 diets (P<0.05). In the Haugh unit for the period of $0~4$$weeks, the AM2 treatment showed significantly improved results compared to the CON (P<0.05). Average egg shell breaking showed no significant differences through the experiment period, but in the period of $4\~8$weeks the AM2 treatment tended to be improved compared to the CON and AM1 treatment (P<0.05). There was no significant differences in egg shell thickness. In the serum cholesterol, the AM1 and AM2 treatments were significantly lower than the CON (P<0.05). The concentration of RBC and WBC in the AM treatments tended to increase but there were no significant differences. For the differences of lymphocytes between the end and initiation of the experiment, the hens fed the AM1 treatment were significantly different compared to the hens fed the CON and AM2 treatment (P<0.05). During the period of the experiment, the hens fed the AM1 diet were tended to show higher DM digestibility than the hens fed the CON and AM2 diet, but it was not statistically different. In conclusion, dieatry fed of Animunin Powder$^{?}$ could improve egg production, egg yolk color, and haugh unit.