• Analytical Science and Technology
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• v.20 no.3
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• pp.255-260
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• 2007

A new method for the simultaneous determination of low molecular weight amines and quaternary ammonium ions based on the separation by IC with a suppressor and the detection by MS with ESI has been developed. The method has been applied to the analysis of a mixture containing tetramethylammonium ion, tetraethylammonium ion, tetrapropylammonium ion, triethanolamine, trimethylamine and triethylamine. The constituents were separated by isocratic elution using an IonPac CS17 column, a cation-exchange column, and detected by conductivity and mass spectrometry. The newly developed method for the six components demonstrated that the repeatability in terms of relative standard deviation for three measurements was in the range of 0.1-0.5 %. The detection limits were between 0.2 and $0.9{\mu}g/mL$ by the IC/ESI-MS.

• Journal of the Korean Society of Safety
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• v.37 no.1
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• pp.41-48
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• 2022

Bridge engineering documents have essential contents that must be referenced continuously throughout a structure's entire life cycle, but research related to the quality of the contents is still lacking. XML schema matching is an excellent technique to improve the quality of stored data; however, it takes excessive computing time when applied to documents with many contents and a deep hierarchical structure, such as bridge engineering documents. Moreover, it requires a manual parametric study for matching elements' weight factors, maintaining a high matching accuracy. This study proposes an efficient weight-factor determination method based on an artificial neural network (ANN) model using the simplified XML schema-matching method proposed in a previous research to reduce the computing time. The ANN model was generated and verified using 580 data of document properties, weight factors, and matching accuracy. The proposed ANN-based schema-matching method showed superiority in terms of accuracy and efficiency compared with the previous study on XML schema matching for bridge engineering documents.

• Polymer(Korea)
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• v.38 no.6
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• pp.735-743
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• 2014

The rheological measurement of polypropylene (PP) has been performed using a rheometer, an intrinsic viscometer, and an MI machine to predict the molecular weight and the molecular weight distribution. Also, GPC has been used for the determination of the molecular structure. The distribution broadness parameter using modified Carreau model has been used to make the correlation between the rheological parameter and the molecular structure instead of the rheological PI (polydispersity index) which is determined from the cross of modulus from the dynamic oscillatory measurement. Even though the rheological PI is useful to determine the molecular weight distribution of the PP using controlled rheology, which has narrow and uniform molecular weight distribution, but not suitable to determine the molecular weight distribution of the PP made from direct polymerization which has broad and various molecular weight distribution. However the distribution broadness parameter which determined from the index of the shear thinning of the PP melt well predicts the molecular weight distribution of PP.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.342-342
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• 2000

We present 3-axis stabilized spacecraft attitude determination algorithm using the magnetometer. The magnetometer has been used as a reliable, light-weight and inexpensive sensor in attitude determination and reaction wheel momentum dumping system. Recent studies have attempted to use the magnetometer when other attitude sensor, such as star tracker, fails. The differences between the measured and computed the Earth's magnetic field components are spacecraft attitude errors. In this paper, we propose extended Kalman filter(EKF) to determine spacecraft attitude with the magnetometer data and gyro-measured body rates. We develop and simulate this algorithm using MATLAB/SIMULINK. This algorithm can be used as a backup attitude determination system.

• The Journal of Internal Korean Medicine
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• v.34 no.4
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• pp.349-361
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• 2013

Objectives : This study aimed to evaluate the single oral dose toxicity and four weeks repeated dose determination of Gamisasangja-tang (GST) in male and female Sprague-Dawley rats. Methods : In the single oral toxicity study, rats were orally administered a single dose of 0 and 5,000 mg/kg GST. There were 5 rats in each group. After single administration, mortality, clinical signs, body weight changes and gross pathological finding were observed for 14 days. In the 4-weeks repeated oral dose determination study, rats were orally administered a single dose of 0, 1,250, 2,500 or 5,000 mg/kg GST. There were 5 rats in each group. Mortality, clinical signs, body weight changes, food consumption and gross pathological finding were observed for 28 days. Organ weight, clinical chemistry and hematology were tested after 28 days. Results : There was no mortality in either of the two studies. There were also no significant differences in clinical sign, body weight, organ weights, hematological or serum chemical parameters between the GST and control groups. Conclusions : The results obtained in this study suggest that the 50% lethal dose of GST is over 5,000 mg/kg, so this finding would be expected to provide scientific evidence for the safety of GST.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.5 no.2
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• pp.167-180
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• 1998

The purpose of this study was to explore the subjective opinions related to the weight control by using Q-methodology. Forty four adults were selected for P-sample from July to August, 1998. The collected data were analyzed by PC Quanl program. The results were as follows : There were 5 types of the adult's opinions about the weight control. Type I(Concern about weight control) : This type believes that there is a problem with general social attitudes, but the weight control it self is necessary. Type II(Health conscious) : This type believes that good health is very important and weight control is way of maintaining and improving good health. Type III(Obsessive) : This type believes that weight control is absolutely necessary no matter what it takes including extreme dietary change. Type IV(Influence by social pressure) : This type believes that the external stimulation and help is needed to motivate weight control. Type V(Self control) : This type believes that self determination is necessary regardless of social pressure.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.2
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• pp.463-474
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• 1995

Modified Vainshtok weight function method is developed. The thermal shock stress intensity factors for elliptical surface cracks existed in the thin and thick walled cylinders are determined. The present results are compared with previous solutions and shown to be good agreement with them.

• Korean Journal of Poultry Science
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• v.49 no.4
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• pp.229-237
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• 2022

This study investigated the growth characteristics of four strains of newly developed synthetic Korean native commercial chickens (KNCs). We investigated a suitable growth curve model in KNCs and estimated the number of days to reach a 2 kg market weight. Body weight was measured at 2-week intervals from birth to 12 weeks of age. The growth curves were estimated using von Berteralanffy, Gompertz, and logistic functions. The results showed that males were significantly heavier than females at all ages, but there were no significant differences in body weight between strains, except at birth and 2 and 6 weeks of age. The coefficients of determination and adjusted determination of growth function had high goodness-of-fit (97.4~99.7). Of the growth curve parameters, the mature weight and growth ratio were higher in males than in females, but the maturity rate was similar in males and females. The inflection point occurred at approximately 7 weeks of age for females and 8 to 9 weeks of age for males. The weights estimated from the growth curve functions almost agreed with the actual weights, except for male weights estimated using the von Bertalanffy function. The coefficients of determination of the regression equations for weight to age were 0.9583 to 0.9746. The 8- and 10-week-old body weights estimated using the regression equation, and the 12-week-old weight estimated using the logistic function were most similar to the actual weight. Using these models, the estimated age of KNCs to reach 2 kg was 62.0~64.6 days for males and 74.9~78.6 days for females.

• Journal of Korea Water Resources Association
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• v.35 no.6
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• pp.685-692
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• 2002

It is very useful to estimate easily the various characteristics of streams and to manage objectively streams, as the order or grade among streams is determined by the natural characteristics and the degree of human utilization. With obtainable various statistics data and expert examination, we proposed the measurable evaluation index of "stream weight" considering the natural characteristics of streams, the utilization degree of streams and the social conditions of the regions crossed streams. The each stream weight is calculated as follows. Firstly, select the various factors which influence to streams in AHP. Secondly, determine the each weight of factors by the result of expert examination. Finally, sum up after multiplying the normalized factors by these two values. The stream weight can be used such divisions as the recognization of relative weight between streams, the determination of the stream management direction in the near future, the enhancement of the efficiency of stream management through the adjustment of the present stream grade and the determination of the management method concerned the stream weight as well.t as well.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.719-723
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• 2002

The purpose of this study is to suggest the correlation of single-number ratings for sound insulation by floor impact. As a assessment method of impact sound insulation. we selected the IIC contour of ISO, A weighted sound level. Inverse A-weighting curve and L-Index of japanese industrial standard. And we estimated the single-number ratings by application the measured data of impact sound level to each method. The results showed that the coefficients of determination between each two single-number ratings were very high (more than 0.9169). And In the condition of same assessment method, the coefficient of determination for light-weight impact sound was higher than that for heavy-weight impact sound.