• 한국식품영양과학회지
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• 제27권3호
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• pp.471-476
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• 1998

The NO3 contents and organophosphorus pesticide residues in edible part of vegetables cultivated by a conventional or an organic farming methods were determined. The NO3 contents of vegetables cultivated by the organic farming method were between 120ppm and 4,523ppm, whereas its contents of vegetables cultivated by the conventional farming method were between 89ppm and 1,575ppm. Fifty two percent of vegetables cultivated by hte organic farming method accumulated NO3 content over than 2,000ppm, whereas 82% vegetables cultivated by the conventional farming method accumulated NO3 content below than 1,000ppm. The NO3 contents of lettuce dependent on the cultivation method obviously. The NO3 contents of lettuce cultivated by a hydroponic farming method were between 4,800 and 6,500ppm, whereas those cultivated by the conventional method were between 630 and 750ppm. The organophosphorus pesticide residues in edible part of vegetables cultivated by the conventional or the organic farming methods were not detected. The NO3 contents in edible part of vegetables cultivated by the organic farming method should be considered as one of several parameters to judge a real safe vegetable to be certified by goverment.

• 전기전자학회논문지
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• 제17권2호
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• pp.151-158
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• 2013

There are several kind of surface deformation display methods using the fuzzy model. In this paper, we describe three fuzzy display methods for a surface deformation and perform a comparative analysis between the modified fuzzy display method and some conventional fuzzy display methods. In each method, the analysis will be performed through computer simulation in order to show the performance of each algorithm. The results show that the modified method have improved the realism and can be used better than the conventional methods in practical applications.

• Communications for Statistical Applications and Methods
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• 제26권5호
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• pp.507-517
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• 2019

Statistical matching is a method of combining multiple sources of data that are extracted or surveyed from the same population. It can be used in situation when variables of interest are not jointly observed. It is a low-cost way to expect high-effects in terms of being able to create synthetic data using existing sources. In this paper, we propose the several statistical micro matching methods using a multinomial logistic regression model when all variables of interest are categorical or categorized ones, which is common in sample survey. Under conditional independence assumption (CIA), a mixed statistical matching method, which is useful when auxiliary information is not available, is proposed. We also propose a statistical matching method with auxiliary information that reduces the bias of the conventional matching methods suggested under CIA. Through a simulation study, proposed micro matching methods and conventional ones are compared. Simulation study shows that suggested matching methods outperform the existing ones especially when CIA does not hold.

• 전기학회논문지
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• 제62권4호
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• pp.482-488
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• 2013

Load forecasting is essential to the economical and the stable power system operations. In general, the forecasting days can be classified into weekdays, weekends, special days and special light-load periods in short-term load forecast. Special light-load periods are the consecutive holidays such as Lunar New Years holidays, Korean Thanksgiving holidays and summer special light-load period. For the weekdays and the weekends forecast, the conventional methods based on the statistics are mainly used and show excellent results for the most part. The forecast algorithms for special days yield good results also but its forecast error is relatively high than the results of the weekdays and the weekends forecast methods. For summer special light-load period, none of the previous studies have been performed ever before so if the conventional methods are applied to this period, forecasting errors of the conventional methods are considerably high. Therefore, short-term load forecast for summer special light-load period have mainly relied on the experience of power system operation experts. In this study, the trends of load profiles during summer special light-load period are classified into three patterns and new forecast algorithms for each pattern are suggested. The proposed method was tested with the last ten years' summer special light-load periods. The simulation results show the excellent average forecast error near 2%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권3호
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• pp.1011-1025
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• 2014

A demosaicing method for a Bayer-like W-RGB color filter array (CFA) is proposed. When reproducing images from a W-RGB CFA, conventional color separation methods for W-RGB CFA are likely to cause blurring near the edges due to rough averaging using a color ratio of neighboring pixels. Moreover, these methods cannot be applied to real-life digital cameras with W-RGB CFA because the methods were proposed under an ideal situation, W=R+G+B, not a real-life situation, $W{\neq}R+G+B$. To improve edge performance, we propose a method of constant color difference assumption with inversed weight, which uses information from all edge directions for interpolating all missing color channels. The proposed method calculates the correlation between W, R, G, and B to enable its application to real-life digital cameras with W-RGB CFA. Simulations were performed to evaluate the proposed method using images captured from a real-life digital camera with W-RGB CFA. Simulation results shows that we can demosaic by using the proposed algorithm compared with the conventional one in about +34.79% SNR, +11.43% PSNR, +1.54% SSIM and 14.02% S-CIELAB error. Thus, the proposed method demosaics better than the conventional methods.

• 한국지반공학회논문집
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• 제28권2호
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• pp.5-14
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• 2012

현장 다짐기에 가속도계를 이용한 연속다짐 평가장치를 부착하여 얻은 지반의 지지력 평가값 및 기존의 다짐도 평가장치의 결과 값들을 회귀분석하여 비교하였다. 회귀분석 평가 결과, 특정 성토재료에서 Geogauge와 동적콘관입시험은 기존 다짐도 평가(평판재하시험 및 다짐도시험) 결과와의 상관관계가 거의 없는 것으로 나타났다. 또한 CMV를 이용한 평가법이 기존 다짐도 평가를 대체할 수 있는지를 알아보기 위하여 여러 가지 다짐도 평가를 실시하였다. 그 결과 가속도계를 이용한 CMV는 다져진 지반의 강성 특성을 빠르고 편리하게 평가할 수 있을 것으로 판단된다.

• Journal of Korean Dental Science
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• 제15권2호
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• pp.132-140
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• 2022

Purpose: Dental diagnostic records derived from study models are a popular method of obtaining reliable and vital information. Conventional plaster models are the most common method, however, they are being gradually replaced by digital impressions as technology advances. Moreover, three-dimensional dental models are becoming increasingly common in dental offices, and various methods are available for obtaining them. This study aimed to evaluate the accuracy of the measurement of dental digital models by comparing them with conventional plaster and to determine their clinical validity. Materials and Methods: The study was conducted on 16 patients' maxillary and mandibular dental models. Tooth size (TS), intercanine width (ICW), intermolar width (IMW), and Bolton analysis were taken by using a digital caliper on a plaster model obtained from each patient, while intraoral scans were manually measured using two digital analysis software. A one-way analysis of variance test was used to compare the dental measurements of the three methods. Result: No significant differences were reported between the TS, the ICW and IMW, and the Bolton analysis through the conventional and two digital groups. Conclusion: Measurements of TS, arch width, and Bolton analysis produced from digital models have shown acceptable clinical validity. No significant differences were observed between the three dental measurement techniques.

• 지질공학
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• 제33권3호
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• pp.439-459
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• 2023

Numerical analysis has been adopted in nearly all modern scientific and engineering fields due to the rapid and ongoing evolution of computational technology, with the number of grid or mesh points in a given data field also increasing. Some values must be extracted from large data fields to evaluate and supplement numerical analysis results and observational data, thereby highlighting the need for a fast and effective interpolation approach. The quadrilateral irregular network (QIN) proposed in this study is a fast and reliable interpolation method that is capable of sufficiently satisfying these demands. A comparative sensitivity analysis is first performed using known test functions to assess the accuracy and computational requirements of QIN relative to conventional interpolation methods. These same interpolation methods are then employed to produce simple numerical model results for a real-world comparison. Unlike conventional interpolation methods, QIN can obtain reliable results with a guaranteed degree of accuracy since there is no need to determine the optimal parameter values. Furthermore, QIN is a computationally efficient method compared with conventional interpolation methods that require the entire data space to be evaluated during interpolation, even if only a subset of the data space requires interpolation.

• 한국지반공학회지:지반
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• 제1권2호
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• pp.75-80
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• 1985

건축물의 연속기초해석에서 종래에는 등분포 접지압을 바탕으로 한 해석방법 위주였다. 좀더 정확한 기초판의 음력해석을 위한 변화접지압을 고려한 해석방법과 기존방법들을 비교.분석해 보고, 더 나아가 기초판에 근응력이 생길 경우 응력을 줄이기 위한 Pontoon식 기초를 소개한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.343-347
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• 1989

In this paper, predictive control method using actual applied input which is the weighted summation of past inputs is presented. In conventional predictive control methods, a set of control inputs is computed and in these only the first element is applied to the process at each time instant. But this predictive control method based on conventional methods considers all computed control inputs. Consequently, the characteristic of response and the reliability of the control scheme in the case of imperfact model are improved.