• 한국전자파학회논문지
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• 제8권4호
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• pp.373-381
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• 1997

디지틀 마이크로파 전송시스템은 다중경로 페이딩에 대한 대응책으로서 등화기를 필수적으로 장착하고 있다. 본 논문에서는 페이딩의 형태에 따라 기준탭의 위치를 가변시키는 기준탭 위치 가변방식 동기화를 제안하였다. 제안된 등화기는 기존의 등화기에 비해 우수한 성능을 나타내는데 MP 상황에서는 약 4~5 dB 정도의 성능개선을 얻을 수 있었으며 NMP 상황에서는 2~3 dB 정도의 성능 개선을 얻을 수 있음을 시뮬레이션 결과를 통하여 증명하였다.

• Journal of Ginseng Research
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• 제17권3호
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• pp.219-223
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• 1993

Assessment of root weight grade system for the numeral definition in Korea ginseng was tried by investigation of 13 boxes of the 15-root-grade of 4-year-old white ginseng as a model. In this case satisfaction to theoretical value was 58% in root weight and 50% in root number. The coefficient of variation (CV) was high (35%) for individual root weight in package. The CV of tap root weight 1 among package is low (7.1%) even though there was no significant correlation between tap root weight : and lateral root weight among roots. The mean percentage of tap root to root weight in each package ranged 61 to 74% with CV range of 16.5 to 33.2%. The CV was not much different between 1st and 2nd lateral root weight and the means was above 60%. Strict practice of numeral definition of root weight grade system will be prerequisite for chemical standardization of Korea ginseng.

• 한국산학기술학회논문지
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• 제19권2호
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• pp.676-682
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• 2018

WSN을 포함하는 IoT 세상이 발전할수록, IoT를 적용하는 주위환경에 따라 정보를 센싱하는 센서 시스템의 수가 매우 가변적이다. 이러한 복잡한 환경에서 각각의 센서 시스템들에 대한 보안을 수행하기 위하여 보안모듈들도 가변적으로 증감을 수행해야 한다. 이러한 문제점은 시스템 효율성과 해킹/크래킹을 고려하였을 경우, 하드웨어/소프트웨어적인 구현을 어렵게 한다. 그러므로 본 논문은 이러한 문제점을 해결하기 위하여 센싱 노드들의 수와 상관없이 일정한 주기를 가지는 의사난수를 발생시키며 이상현상을 탐지할 수 있는 기능을 가진 고정 길이 탭을 가진 의사 난수 발생기(FLT: Pseudo-random Number Generator with Fixed Length Tap unrelated to the variable sensing nodes) 구조를 제안하였다. 제안된 FLT-LFSR 구조는 IoT 환경에서 하드웨어/소프트웨어 구현에 대하여 보안레벨 및 전체 데이터 포맷팅을 일정하게 유지시킬 수 있도록 하였다. 그러므로 제안된 FLT-LFSR 구조는 센서 시스템 구현의 용이성 및 센싱 노드들의 수와 상관없이 네트워크의 확장성을 강조할 수 있도록 하였다.

• Archives of Pharmacal Research
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• 제29권5호
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• pp.418-423
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• 2006

Tabanus anticoagulant protein (TAP) was isolated from the whole body of the tabanus, Tabanus bivittatus, using three purification steps (ammonium sulfate fractionation, gel filtration on Bio-Gel P-60, and ion exchange chromatography on DEAE Sephadex gel). The purified TAP, with a molecular weight of 65 kDa, was assessed to be homogeneous by SDS-polyacrylamide gel electrophoresis, and an isoelectric point of 7.9 was determined by isoelectric focusing. The internal amino acid sequence of the purified protein was composed of Ser-Leu-Asn-Asn-Gln-Phe-Ala-Ser-Phe-lle-Asp-Lys-Val-Arg. The protein was activated by $Cu^{2+}\;and\;Zn^{2+}$, and the optimal conditions were found to be at pH $3\sim6\;and\;40\sim70^{\circ}C$. Standard coagulation screen assays were used to determine thrombin time and activated partial thromboplastin time. Chromogenic substrate assays were performed for thrombin and factor Xa activity. TAP considerably prolonged human plasma clotting time, especially activated partial thromboplastin time in a dose-dependent manner; it showed potent and specific antithrombin activity in the chromogenic substrate assay. Specific anti-factor Xa activity in TAP was not detected. Overall, this result suggested that TAP has significant anticoagulant activity on blood coagulation system.

• 한국물환경학회지
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• 제20권3호
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• pp.281-289
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• 2004

Optimal analytical conditions have been established for mixing and reaction coil length, concentrations of ECR, CTAB, and acetate, reaction temperature and pH in the determination of aluminum by using flow injection analysis(FIA). Detection limit and repeatability for this system were $3{\mu}g/L$ and better than 1% of relative standard deviation, respectively. The interference from iron(III) was suppressed up to 6mg/L of iron(III) by $0.1{\mu}M$ ascorbic acid, and the interference from fluoride could be tolerated in absorption of Al/ECR/CTAB derivative by 10mM boric acid at pH 3.5 adjusted with nitric acid. This FIA system was applied to the determination of aluminum leached from cooking utensils by distilled and tap water containing fluoride ranged from 0.5 to 2mg/L by measurement of absorbance for Al/ECR/CTAB at 585nm. The leached aluminum content was increased with increasing concentration of fluoride. The aluminum contents leached from aluminum utensils by tap water were about 9 fold higher than those leached by distilled water, whereas aluminum contents leached by distilled water containing fluoride were about 2 fold higher compared to those leached by distilled water. That represented that other dissolved substances as well as fluoride in tap water contributed to liberation of aluminum from aluminum utensils. A comparison between FIA data and ICP-AES data by correlation and paired t test showed that the FIA system could be accepted as a good alternative method for the determination of aluminum in tap water.

• 환경위생공학
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• 제9권2호
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• pp.50-57
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• 1994

Densities of total and injured coliforms in treated water( TW ) and three tap water salt pies( Taps Kl, K2 and K3) of Ku- eui water treatment plant and one tap water sample( Tap T) of Tuk- do water treatment plant were measured 23 times from 1991 to 1992. Coliform regrowth in the water distribution system occurred three times during the study period. When the regrowth episode occurred, injured coliforms were always but total coliforms were not always detected in treated water. Mean densities of total coliforms in TW, and Taps Kl, K2, K3 and T were 0.8, 2.3, 1.9, 1.4 and 2.1 cfu/100mℓ by membrane filtration method using m- TF agar and those of injured coliforms were 3.4, 2.8, 2.5, 2.7 and 2.9 c1u/100mℓ using mondo- LES agar. The injury rates of TW and Taps Kl, K2, K3 and T were 89.5,77.4,67.9, 82.8 and 75.9%, respectively. The high injury rate of coliform bacteria in Seoul water supply can cause regrowth problems in distribution systems due to the repair of injured cells under an appropriate condition. It is recommended the injured coliforms should be measured in drinking water since they can lead to a significant underestimation of total coliforms and result in an inaccurate evaluation of the potential health risks.

• 미생물학회지
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• 제31권3호
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• pp.245-254
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• 1993

1991년 9월부터 1992년 9월까지 23회에 걸쳐 서울시 구의정수장의 상수도계통 즉 원수와 정수 및 이곳에서 공급되는 단일 배급수계통의 3개 수돗물에서 종속영양세균(heterotrophic plate count : HPC) 과 장내세균(Enterobacteriaceae : total coliforms) 의 분포를 조사하였다. $R_{2}A$ 한천배지에서의 종속영양세균수는 원수 $1.22{\times}10^{3}~3.05{\times}10^{5}$ 정수 $1.50{\times}10^{1}~4.29{\times}10^{3}$, 수돗물 $2~5.41{\times}10^{3}$ cfu/100ml, 수돗물 0-47.5 cfu/100 ml 의 범위였으며, m-T7 한천배지에서의 손상된장내세균을 포함하는 장내세균수는 전수 0-27, 수돗물 0-35 cfu/100 ml/의 범위였다. 이러한 결과로부터 정수장에서 공급된 물이 배급수관을 통하여 공급되면서 종속영양세균 및 장내세균의 개체수가 증가하는 세균재생장 현상이 발생한다는 것을 확인하였다. 종속영양세균의 동정결과 원수, 정수, 수돗물을 포함하는 상수도계통의 물에서는 Peudomonas 와 Acinetobacter 가 우점하였으나, 원수에서는 Pseudomonas 의 비율이, 그리고 정수와 수돗물에서는 Acinetobacter 의 비율이 상대적으로 높은 것으로 나타났다. 장내세균은 Enterobacter agglomerans 가 우점종이었으며, 수돗물에서는 정수에서 검출되지 않았던 Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, Shigella dysenteriae 등의 기회성 및 병원성 장내세균도 검출되었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1042-1047
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• 2004

Voltage control is an essential part of the electric energy transmission and distribution system to maintain proper voltage limit at the consumer's terminal. Besides the generating units that provide the basic voltage control, there are many additional voltage-controlling agents e.g., shunt capacitors, shunt reactors, static VAr compensators, regulating transformers mentioned in [1], [2]. The most popular one, among all those agents for controlling voltage levels at the distribution and transmission system, is the on-load tap changer transformer. It serves two functions-energy transformation in different voltage levels and the voltage control. Artificial Neural Network (ANN) has been realized as a convenient tool that can be used in controlling the on load tap changer in the distribution transformers. Usage of the ANN in this area needs suitable training and testing data for performance analysis before the practical application. This paper briefly describes a procedure of processing the data to train an Artificial Neural Network (ANN) to control the tap changer operating decision of parallel transformers for a closed primary bus. The data set are used to train a two layer ANN using three different neural net learning algorithms, namely, Standard Backpropagation [3], Bayesian Regularization [4] and Scaled Conjugate Gradient [5]. The experimental results are presented including performance analysis.

• 환경위생공학
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• 제10권1호
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• pp.106-125
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• 1995

Recently, in accordance with elevation of life style and economics, the public demand became increasingly concerned about drinking water quality. Without an adequate supply of safe water, healthy and comfortable life could not exist. Therefore, the purpose of this study is to provide the guidelines and the basic informations to enable supply of clean, tasty and healthy drinking water acceptable for various demands. We analyzed the quality of tap water, mineral water, purified tap water using home tap water purifier. And we researched on the sense of the public complaint over the tap water. We proposed several items relating to the comfortableness of water quality and the target value. Also we presented a case of water supply system for purity and the points at problem The items and target value are as follows 1. turbidity : not more than 1 degree 2. dry residue : $30~200{\;}mg/{\ell}$ 3. hardness : $10~100mg/{\ell}$ 4. free carbon dioxide : not more than $20mg/{\ell}$ 5. $KMnO_{4}$ consumption not more than $3mg/{\ell}$ 6. odor threshold not abnormal 7. residual chlorine : not more than $0.4mg/{\ell}$ 8. water temperature' not more than $20^{\circ}C$ 9. manganese : not more than $0.01mg/{\ell}$ 10. iron : not more than $0.02mg/{\ell}$ 11. aluminum : not more than $0.1mg/{\ell}$

• 한국식품조리과학회지
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• 제23권4호통권100호
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• pp.567-578
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• 2007

This study was designed to provide basic data for the application and practical use of vinegar disinfection for raw vegetable preparation in foodservice operations. The test materials were washed and disinfected by three different methods(tap water washing, chlorine water disinfection, vinegar disinfection) and stored at $3^{\circ}C$ and $10^{\circ}C$ for 7 days. Then, their microbiological qualities were compared. Total plate counts increased over the course of the storage period, and all samples, except in the case of tap water washing, remained under the permitted limit until the 7th day of storage. In particular, vinegar disinfection showed the lowest increase in total plate counts(2.35${\sim}$4.03 log CFU/g). While the total plate counts of chlorine and vinegar disinfection were within the 6.00 limit of microbiological safety, the tap water washing treatment passed the permitted limit. The psychrotrophic counts increased steadily over the course of the storage period, and increased least at $3^{\circ}C$, however, the tap water washing showed the most drastic increase, while vinegar disinfection yielded the smallest increase.