• Analytical Science and Technology
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• v.6 no.1
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• pp.93-106
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• 1993

Fragmentation patterns on electron impact of 8 chlorinated organophosphorus pesticides were investigated. In most cases, characteristic ions could e identified and the peak clusters due to the $^{35}Cl$ and $^{37}Cl$ isotopes in the fragment ions were found to be highly characteristic. The fragmentation patterns of phosphorus moiety were coincident with previous report in the aspect of mechanism.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.76.1-76.1
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• 2014

We investigate the solar flare and CME occurrence rate and probability depending on sunspot class and its area change. These CMEs are front-side, partial and full halo CMEs associated with X-ray flares. For this we use the Solar Region Summary(SRS) from NOAA, NGDC flare catalog, and SOHO/LASCO CME catalog for 16 years (from January 1996 to December 2011). We classify each sunspot class into two sub-groups: "Large" and "Small". In addition, for each class, we classify it into three sub-groups according to sunspot class area change: "Decrease", "Steady", and "Increase". In terms of sunspot class area, the solar flare and CME occurrence probabilities noticeably increase at compact and large sunspot groups (e.g., 'Fkc'). In terms of sunspot area change, solar flare and CME occurrence probabilities for the "Increase" sub-groups are noticeably higher than those for the other sub-groups. For example, in case of the (M+X)-class flares of 'Dkc' class, the flare occurrence probability of the "Increase" sub-group is three times higher than that of the "Steady" sub-group. In case of the 'Eai' class, the CME occurrence probability of the "Increase" sub-groups is five time higher than that of the "Steady" sub-group. Our results demonstrate statistically that magnetic flux and its emergence enhance solar flare and CME occurrence, especially for compact and large sunspot groups.

• Journal of the Korean Institute of Gas
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• v.2 no.1
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• pp.83-89
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• 1998

Experiments had been conducted Qualitatively regarding flow measurement errors of orifice flowmeter due to temperature difference between the inside and outside the natural gas meter-run in case of no pipe insulations. The primary factors considered in this study are fluid velocity and surrounding temperature. In addition, a portion of thermal radiation due to the sun was involved as a factor. The results showed that the considerable errors were not detected even in conditions of low flow rates and large temperature difference between the inside and outside the meter-run.

• Korean Journal of Agricultural Science
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• v.50 no.3
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• pp.485-496
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• 2023

In this study, we aimed to apply multispectral imaging (713 - 920 nm, 10 bands) for maturity classification and recognition of oriental melons grown in hydroponic greenhouses. A total of 20 oriental melons were selected, and time series multispectral imaging of oriental melons was 7 - 9 times for each sample from April 21, 2023, to May 12, 2023. We used several approaches, such as Savitzky-Golay (SG), standard normal variate (SNV), and Combination of SG and SNV (SG + SNV), for pre-processing the multispectral data. As a result, 713 - 759 nm bands were preprocessed with SG for the maturity classification of oriental melons. Additionally, a Light Gradient Boosting Machine (LightGBM) was used to train the recognition model for oriental melon. R² of recognition model were 0.92, 0.91 for the training and validation sets, respectively, and the F-scores were 96.6 and 79.4% for the training and testing sets, respectively. Therefore, multispectral imaging in the range of 713 - 920 nm can be used to classify oriental melons maturity and recognize their fruits.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.84.2-84.2
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• 2015

There are probabilistic forecast models for solar flare occurrence, which can be evaluated by various skill scores (e.g. accuracy, critical success index, heidek skill score, true skill score). Since these skill scores assume that two types of forecast errors (i.e. false alarm and miss) are equal or constant, which does not take into account different situations of users, they may be unrealistic. In this study, we make an evaluation of a probabilistic flare forecast model (Lee et al. 2012) which use sunspot groups and its area changes as a proxy of flux emergence. We calculate daily solar flare probabilities from 1996 to 2014 using this model. Overall frequencies are 61.08% (C), 22.83% (M), and 5.44% (X). The maximum probabilities computed by the model are 99.9% (C), 89.39% (M), and 25.45% (X), respectively. The skill scores are computed through contingency tables as a function of forecast probability, which corresponds to the maximum skill score depending on flare class and type of a skill score. For the critical success index widely used, the probability threshold values for contingency tables are 25% (C), 20% (M), and 4% (X). We use a value score with cost/loss ratio, relative importance between the two types of forecast errors. We find that the forecast model has an effective range of cost/loss ratio for each class flare: 0.15-0.83(C), 0.11-0.51(M), and 0.04-0.17(X), also depending on a lifetime of satellite. We expect that this study would provide a guideline to determine the probability threshold for space weather forecast.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.93-99
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• 1993

This study was conducted to investigate the cause of a new duck disease occured in southern part of Korea. A meat type duck farm located in Kangjin, Chonnam Province had experienced outbreaks of septicemic disease at around 20 days of age in nearly every batch of ducklings from early spring to early summer in 1989. Main symptoms of the birds were eye and nasal discharge, depression, inappetence, diarrhea and nervous signs such as tremor and ataxia. Some birds died suddenly without any signs. Mortality reached from 20% to 80% in severe cases. The autopsy findings of the affected ducklings revealed consistantly severe airsacculitis, fibropericarditis, perihepatitis and occasionaly enteritis and distended ureter with urate deposit. A rod shaped gram-negative bacterium was isolated purely from brain and liver of the diseased ducks by culturing the specimens on blood agar for 48 hours in candle jar. The isolate neither produced hemolysis nor grew on MacConKey Agar. It formed colony relatively slowly being recognizable at least 36 hours after culturing, reaching colony size of about 1mm in diameter at 48 hours culture. The colony looked iridescent under oblique light and had muddy odor. The isolate did not ferment carbohydrates tested but produced gelatinase, hippuricase and oxidase which were considered as characteristics of P anatipestifer. The isolate induced similar signs and lesions when infected experimentally into ducks of 3 to 38 days age via intraperitoneum or intratrachea. However it did not produce any clinical signs wen inoculated via intranasal route. It produced only mild signs in chicken just injected with a very large dose. The bacteria did not produce any signas or lesions in mice. It was concluded through biochemical and physiological tests and animal inoculation tests that the new disease was caused by P anatipestifer.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.1-8
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• 2002

Seasonal changes in biochemical composition of Crassostrea giggas and Scapharca broughtonii in the Kosong bay and Kangjin bay, southern Korea were studied over 12 months in relation to their habitat. In Crassostrea giggas, protein was high during summer in all experimental station, but lipid and carbohydrate were high during winter, and no clear difference was between experimental station. Glycogen content was sharply decreased during summer, and energy content was low but carbohydrate was high during summer. In Scapharca broughtonii, protein was low, but carbohydrate was high during summer. Lipid was high from February to March, glycogen content was low from June to September. Energy content was low during winter and no clear difference biochemical composition was between experimental station of Scapharca broughtonii.

• Korean Journal of Veterinary Research
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• v.28 no.2
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• pp.299-305
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• 1988

The phenotypes of hemoglobin, albumin and transferrin of 3U2 Jindo dogs in Jindo area were studied by starch gel electrophoresis for hemoglobin and albumin, and by polyacrylamide gradient gel electrophoresis for transferrin. The results obtained were as follows: 1. In the hemoglobin phenotypes, three phenotypes, HbAA, HbAB and HbBB, which were controlled by two allelic genes, $Hb^A$ and $Hb^B$, were observed and their frequencies of appearance were 1.65%, 10.60% and 87.75% respectively. The distribution of gene frequency was calculated as 0.0695 in $Hb^A$ and 0.9305 in $Hb^B$. 2. In the albumin phenotypes, three phenotypes, Alb FF, Alb FS and Alb SS, which were controlled by two allelic genes, $AIb^F$ and $AIb^S$ were observed and their frequencies of appearance were 12.59%, 25.56% and 61.85% respectively. The distribution of gene frequency was calculated as 0.2537 in $AIb^F$ and 0.7463 in $AIb^S$. 3. Analysis of transferrin phenotypes showed 6 different types which were controlled by three allelic genes, $Tf^B$, $Tf^C$ and $Tf^D$ and their frequencies of appearance were 54.04% in TfBB, 17.54% in TfBC, 9.82% in TfBD, 8.07% in TfCC, 7.37% in TfCD and 3.16% in TfDD. The distribution of gene frequency was calculated as 0.6772 in $Tf^B$, 0.2053 in $Tf^C$ and 0.1175 in $Tf^D$.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.184-193
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• 2014

Purpose: The aim of this study was to develop a technique for the non-destructive and rapid prediction of the moisture content in red pepper powder using near-infrared (NIR) spectroscopy and a partial least squares regression (PLSR) model. Methods: Three red pepper powder products were separated into three groups based on their particle sizes using a standard sieve. Each product was prepared, and the expected moisture content range was divided into six or seven levels from 3 to 21% wb with 3% wb intervals. The NIR reflectance spectra acquired in the wavelength range from 1,100 to 2,300 nm were used for the development of prediction models of the moisture content in red pepper powder. Results: The values of $R{_V}{^2}$, SEP, and RPD for the best PLSR model to predict the moisture content in red pepper powders of varying particle sizes below 1.4 mm were 0.990, ${\pm}0.487%$ wb, and 10.00, respectively. Conclusions: These results demonstrated that NIR spectroscopy and a PLSR model could be useful techniques for measuring rapidly and non-destructively the moisture content in red pepper powder.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.404-410
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• 2012

Purpose: The objective of this research was to select high quality cucumber (cucumis sativus) seed by classifying into viable or non-viable one using Raman spectroscopy. Method: Both transmission and back-scattering Raman spectra of viable and non-viable seeds in the range from $150cm^{-1}$ to $1890cm^{-1}$ were collected with a laser illumination. Results: The Raman spectra of cucumber seed showed Raman peaks with features of polyunsaturated fatty acids. The partial least squares-discriminant analysis (PLS-DA) to predict viable seeds was developed with measured transmission and backscattering spectra with Raman spectroscopy and germination test results. Various types of spectra pretreatment were investigated to develop the classification models. The results of developed PLS-DA models using the transmission spectra with mean normalization or range normalization, and back-scattering spectra with mean normalization treatment or baseline correction showed 100% discrimination accuracy. Conclusions: These results showed that Raman spectroscopy technologies can be used to select the high quality cucumber seeds.