• Journal of the korean Society of Automotive Engineers
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• v.6 no.2
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• pp.55-63
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• 1984

Berglund-Liu 진동방식 단분산 분체입자 발생기(Berglund-Liu vibrating orifice monodisperse aerosol generator)에 의하여 제작한 단분산 광흡수성 표준분체입자를 사용하여 레이저 산란광 분체입도 측정기 (Knollenberg active scattering aerosol spectrometer)의 반응특성을 조사하 였다. 실험결과, 기기의 반응특성은 Mie 산란이론에 의하여 계산한 이론치와 매우 잘 일치하며 특히 광흡수성 분체입자는 광통과성 분체입자가 다의적인 특성을 나타내는 것에 반하여 거의 단조증가하는 일의적인 특성을 가지고 있으며 광흡수성 분체입자의 반응특성이 제작자의 교정 치에 가까운 결과를 나타내었다.

• Korean Journal of Optics and Photonics
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• v.4 no.4
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• pp.381-389
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• 1993

A software to calculate diffraction OTF from lens design data was developed and its accuracy was verified. To verify the accuracy, MTF of a standard lens system for OTF measurement were calculated. The results were compared with calculated values by another commercial software and measured values. We found that they have good agreements with one another.

• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.219-222
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• 2008

본 논문에서는 WDM시스템에서 사용될 수 있는 광전치증폭기의 수신감도를 해석하였다. $10^{-9}$의 에러확률에 대하여 FSK전송을 이용하여 비트당 광자수를 계산하여다. 결과로 일반적인 PIN 수신기의 수신감도는 $9.2{\times}10^4$ photon/bit이고, 광전치증폭수신기의 경우는 $7{\times}10^2$의 phton/bit를 갖음을 확인하였다. 또한 FSK전송의 경우에는 표준에러확률인 $10^{-9}$을 유지하기 위해 필요로 하는 비트당 광자의 수를 계산하였는데, 가우시안 근사해석법을 사용한 경우와 정확한 해석법(k자승법)을 이용한 결과 m=30인 경우 k자승법의 경우는 $2.36{\times}10^2$ photon/bit, 가우시안 근사법의 경우에는 $4.01{\times}10^2$ photon/bit을 얻었다. 이를 통해 동일한 BER의 경우에 광전치증폭수신기가 PIN수신기에 비해 우수함을 확인하였다.

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.8
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• pp.406-413
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• 2001

본 논문은 CMOS 디지털 회로에서 글리치(glitch)에 의해 발생하는 전력소모를 줄이기 위한 효율적인 휴리스틱 알고리즘을 제시한다. 제안된 알고리즘은 사이징되는 게이트의 위치와 양에 따라 게이트 사이징을 세 가지 type으로 분류한다. 또한 버퍼삽입은 삽입되는 버퍼의 위치에 따라서 두 가지 type으로 분류한다. 글리치 제거 효과를 극대화하기 위해서 비용과 이득의 상관관계를 고려하여 하나의 최적화 과정 안에서 세 가지 type의 게이트 사이징과 두 가지 type의 버퍼삽입을 혼합한다. 제안된 알고리즘은 0.5$\mu\textrm{m}$ 표준 셀 라이브러리(standard cell library)를 이용한 LGSynth91 벤치마크 회로에 대한 테스트 결과 효율성을 검증하였다. 실험결과는 평균적으로 69.98%의 글리치 감소와 28.69%의 전력감소를 얻을 수 있었으며 이것은 독립적으로 적용된 게이트 사이징과 버퍼 삽입 알고리즘에 의한 것 보다 좋은 결과이다.

• 대한예방의학회:학술대회논문집
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• 1998.10b
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• pp.52-55
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• 1998

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.23-27
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• 1996

$\beta$-선 흡수선량의 1차 표준이 확립되지않은 상황에서 측정표준이 이미 확립된 외국의 표준기관에서 검증되어 도입된 $\beta$-선 흡수선량 조사시설에 대해 ISO-6980에서 명시한 항목에 대해 성능실험을 수행하였고, 외삽형전리함을 사용하여 측정된 이온화전류로 부터 흡수선량률을 재평가하여 외국의 검증결과와 비교하였다. 조사시설의 성능실험 결과 Sr$^{90}$ +Y$^{90}$ 선원에 대해 선원으로부터 30cm거리에서 빔 균일도, 제동복사선 기여도 및 $\beta$-선 최대잔여에너지가 기준에 적합한 것으로 나타났다. 그리고 흡수선량 평가결과는 '96. 4. 1을 기준으로하여 20 $^{\circ}C$,1기압에서 2.686 ($\pm$2.73%)$\mu$Gy/sec로 외국표준기관의 측정치와 1.8%이내에서 일치하는 것으로 나타났다.

• Applied Biological Chemistry
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• v.10
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• pp.1-13
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• 1968

Phytin is a salt(mainly calcium and magnesium) of phytic acid and its purity and molecular formula can be determined by assaying the contents of phosporus, calcium and magnesium in phytin. In order to devise a new method for the quantitative analysis of the three elements in phytin, the chelatometric method was developed as follows: 1) As the pretreatment for phytin analysis, it was ashfied st $550{\sim}600^{\circ}C$ in the presence of concentrated nitric acid. This dry process is more accurate than the wet process. 2) Phosphorus, calcium and megnesium were analyzed by the conventional and the new method described here, for the phytin sample decomposed by the dry process. The ashfied phytin solution in hydrochloric acid was partitioned into cation and anion fractions by means of a ration exchange resin. A portion of the ration fraction was adjusted to pH 7.0, followed by readjustment to pH 10 and titrated with standard EDTA solution using the BT [Eriochrome black T] indicator to obtain the combined value of calcium and magnesium. Another portion of the ration fraction was made to pH 7.0, and a small volume of standard EDTA solution was added to it. pH was adjusted to $12{\sim}13$ with 8 N KOH and it was titrate by a standard EDTA solution in the presence of N-N[2-Hydroxy-1-(2-hydroxy-4-sulfo-1-naphytate)-3-naphthoic acid] diluted powder indicator in order to obtain the calcium content. Magnesium content was calculated from the difference between the two values. From the anion fraction the magnesium ammonium phosphate precipitate was obtained. The precipitate was dissolved in hydrochloric acid, and a standard EDTA solution was added to it. The solution was adjusted to pH 7.0 and then readjusted to pH 10.0 by a buffer solution and titrated with a standard magnesium sulfate solution in the presence of BT indicator to obtain the phosphorus content. The analytical data for phosphorus, calcium and magnesium were 98.9%, 97.1% and 99.1% respectively, in reference to the theoretical values for the formula $C_6H_6O_{24}P_6Mg_4CaNa_2{\cdot}5H_2O$. Statical analysis indicated a good coincidence of the theoretical and experimental values. On the other hand, the observed values for the three elements by the conventional method were 92.4%, 86.8% and 93.8%, respectively, revealing a remarkable difference from the theoretical. 3) When sodium phytate was admixed with starch and subjected to the analysis of phosphorus, calcium and magnesium by the chelatometric method, their recovery was almost 100% 4) In order to confirm the accuracy of this method, phytic acid was reacted with calcium chloride and magnesium chloride in the molar ratio of phytic: calcium chloride: magnesium chloride=1 : 5 : 20 to obtain sodium phytate containing one calcium atom and four magnesium atoms per molecule of sodium phytate. The analytical data for phosporus, calcium and magnesium were coincident with those as determine d by the aforementioned method. The new method employing the dry process, ion exchange resin and chelatometric assay of phosphorus, calcium and magnesium is considered accurate and rapid for the determination of phytin.

• Microbiology and Biotechnology Letters
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• v.20 no.3
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• pp.355-361
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• 1992

In order to evaluate an enzyme-linked immunosorbent assay(ELISA) for practical use in detecting aflatoxin $B_1(AFB_1)$ from cereals, we compared $AFB_1$ concentrations of samples contaminated artificially or naturally that were quantitated by the ELISA with those spiked or quantitated by HPLC. Cotton seed meals(19 items), rape seed meals(ll), soybean meals(9), and corns(3) imported from foreign countries were used as sample cereals. The standard curves of each cereal class showed that 1-100 ng/g of $AFB_1$ from cereals could be assayed by the ELISA. When artificially contaminated cereals were assayed by ELISA, the average recovery of AFB! from samples spiked to 3 ng/g and more was 138%(68-193%), although that spiked to 1 ng/g was somewhat high(268%). The average C.V. of recovery was 7.0%(0-22.2%). When naturally contaminated cereals were assayed, the concentrations of $AFB_1$ below 10 ng/g especially from rape seed meals quantitated by ELISA were much lower than those determined by HPLC. However, the concentrations of 10 ng/g and more from samples, except a few extraordinary samples. quantitated by ELISA were similar to those determined by HPLC, especially in case of cotton seed meals whose average recovery (ELISA/HPLC) was 153%. In conclusion, the ELISA was elucidated such as a practical tool to detect $AFB_1$ of 10 ng/g and more from cereals.

• Smart Media Journal
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• v.13 no.4
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• pp.48-56
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• 2024

In the livestock industry, detecting environmental outliers and predicting data are crucial tasks. Outliers in livestock environment data, typically gathered through time-series methods, can signal rapid changes in the environment and potential unexpected epidemics. Prompt detection and response to these outliers are essential to minimize stress in livestock and reduce economic losses for farmers by early detection of epidemic conditions. This study employs two methods to experiment and compare performances in setting thresholds that define outliers in livestock environment data outlier detection. The first method is an outlier detection using Mean Squared Error (MSE), and the second is an outlier detection using a Dynamic Threshold, which analyzes variability against the average value of previous data to identify outliers. The MSE-based method demonstrated a 94.98% accuracy rate, while the Dynamic Threshold method, which uses standard deviation, showed superior performance with 99.66% accuracy.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.83-90
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• 2007

In this paper, we propose an implementation and an algorithm of 'Jitter and Glitch Removing Circuit' for UHF RFID reader system based on ISO/IEC 18000-6C standard. We analyze the response of TI(Texas Instrument) Gen2 tag with a reader using the proposed algorithm. In ISO/IEC 18000-6C standard, a bit rate accuracy(tolerance) is up to +/-22% during tag-to-interrogator communication and +/-1% during interrogator-to-tag communication. In order to solve tolerance problems, we implement the Jitter and Glitch Removing Circuit using the concept of tolerance and tolerance-accumulation instead of PLL(DPLL, ADPLL). The main clock is 19.2MHz and the LF(Link Frequency) is determined as 40kHz to meet the local radio regulation in korea. As a result of simulations, the error-rate is zero within 15% tolerance of tag responses. And in the case of using the adaptive LF generation circuit, the error-rate varies from 0.000589 to zero between 15% and 22% tolerance of tag responses. In conclusion, the error-rate is zero between 0%-22% tolerance of tag response specified in ISO/IEC 18000-6C standard.