• Analytical Science and Technology
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• v.28 no.5
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• pp.323-330
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• 2015

Alkaptonuria, a rare inherited metabolic disease, is characterized by a lack of homogentisate dioxygenase and accumulation of homogentisic acid (HGA), leading to homogentisic aciduria, arthritis, and ochronosis. In this study, a rapid analytical method, without an expensive and tedious solid phase extraction step, was developed to quantify HGA in plasma using GC-MS. HGA-spiked pooled plasma samples were subjected to liquid-liquid extraction (LLE) with ethyl acetate, followed by trimethylsilyl derivatization (TMS) and GC-MS quantification using selected ion monitoring. The formation of TMS derivative of the 1 carboxylic and 2 hydroxyl functional groups was performed by reacting BSTFA (with 10% TMCS) for 5 min at 80 ℃. For selected ion monitoring, quantification and confirmation ions were determined based on specific ions (m/z 384, m/z 341 and m/z 252) of the TMS derivative of HGA. Calibration curves of pooled normal plasma specimens showed a linear relationship in the range of 1-100 ng/µL. The precision and accuracy were within a relative standard deviation (RSD) of 1 to 15% and a bias of -5 to 25%. Recoveries were obtained in the range of 99-125% and 95-115% for intra-day and inter-day assay, respectively, at 2, 20 and 80 ng/µL. The limit of detection (LOD) and limit of quantification (LOQ) were 0.4 ng/µL and 4 ng/µL, respectively. No homogentisic acid was excreted from normal Korean plasma samples. Collectively, the results from the present study suggest that this method could be useful for routine diagnosis and therapeutic monitoring of alkaptonuria patients with excellent sensitivity and rapidity.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.173-185
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• 2018

Effects of three different types of dispersions and flow improving additives composed with fatty acid esters, fatty acid metal salts and amide compound on the vulcanization and the mechanical properties properties of rubber compounds of EPDM and carbon black as fillers. were investigated using Mooney viscometer, moving die rheometer, hardness tester, and universal test machine. The aging characteristics of vulcanized EPDM compounds were also investigated. The Mooney viscosity measured at $125^{\circ}C$ showed a tendency to decrease in the order of amide type> metal salt type > ester type additive. Scorch time showed little or no difference with the addition of ester or metal salt type additives, but the amide type additive shortened a scorch time more than one minute. Rheological measurement data obtained at $160^{\circ}C$ showed that the vulcanization time was faster for metal salt type and amide type additive systems. Delta torque values of EPDM compound increased with metal salt type and amide type additives, but slightly decreased with ester type additive. The tensile strength of the EPDM compound was greatly improved when an ester type additive was added, but the amide type or metal salt type additive had no significant effect. The elongation was significantly improved for metal salt type additive, while the rest were not significantly affected. The tear strength of the EPDM compounds increased with the addition of all kinds of additives, and it increased remarkably in the case of metal salt type additive. Hardness of the EPDM compounds was nearly same value regardless of additive types. The thermal aging of the EPDM blend at $100^{\circ}C$ for 24 h showed little change in the case of metal salt type or amide type additive, but the elongation tends to decrease by 10-20% for all EPDM compounds containing additives.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.241-250
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• 1992

This study was covered the amount of food consumed per day as well as methods estimating the daily food consumption per fish of Agrammus agrammus in natural population to understand flow of food organisms among trophic levels in bio-community of the coastal waters, Shinsudo, Samchonpo. The estimating formulas were induced from the mathematical models that representing the diurnal fluctuation of the stomach fullness of the fish. The daily food consumption could be estimated by both feeding rates and gastric evacuation rates, but it was more reasonable method that based on gastric evacuation rates than feeding rates. The daily food consumption in wet weight per fish by gastric evacuation rates were 1.9856g/day, 3.4725g/day, 4.4418g/day, 5.8168g/day, and 7.2113g/day in the order of age groups from 0 to 4. The daily rations as percentage of body weight were $9.35\%,\;6.65\%,\;5.76\%,\;4.72\%\;and\;5.31\%$ in the order of ages. The daily food consumption was proportional to the body weight of fish, but the daily food consumption per specific body weight was reciprocal to the body weight. Annual food consumption in wet weight. per fish by gastric evacuation rates were 529.98g from the age of 0.25 to 1.0, 1,269.28g from the age of 1.0 to 2.0, 1,622.76g from the age of 2.0 to 3.0, 2,125.57g from the age of 3.0 to 4.0, 1,316.09g from the age of 4.0 to 4.5 The amount of food consumed per fish during 4.25 years, from the age of 0.25 to 4.5, was 6,863.68g in wet weight. the relationships between the daily food consumption(Dr) by gastric evacuation rates and the total length(L, cm) or the body weight(W, g) were as follows: $$Dr=0.036L^{1.702}$$ $$Dr=0.254W^{0.664}$$

• Food Science and Preservation
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• v.23 no.4
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• pp.453-458
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• 2016

'Jonathan' apples are relatively small size which contributes to enhancing fruit consumption and gaining popularity. Thus, this study was carried out to evaluate the effects of AVG (aminoethoxyvinylglycine, ReTain$^{(R)}$), sprayable 1-MCP (1-methylcyclopropene, Harvista$^{TM}$), and fumigation 1-MCP (SmartFresh$^{TM}$) applications on fruit quality attributes and storability in 'Jonathan' apple fruits during cold-stored. The Jonathan fruits were dipped with either ReTain (75 mg/L) or Harvista (125 mg/L) solutions for 5 min, or fumigated with SmartFresh (1 mg/L) for 18 hr before storage at $0{\pm}1^{\circ}C$ for 75 days. Flesh firmness and titratable acidity remained higher in all pre-treated apples than control ones during cold storage period. Flesh firmness was higher for apples treated with ReTain and SmartFresh than samples treated with Harvista, while soluble solid content and respiration rate were not affected by sample pretreatment. Internal ethylene concentration (IEC) of all pretreated apples remained below about $4.5{\mu}L/L$ during the entire storage period while that of control sample greatly increased to $10.29{\mu}L/L$. Ethylene production was much higher in control fruits than in treated ones during cold storage. These results indicated that ReTain and 1-MCP treatments would be considerably effective in retention of fruit quality attributes of 'Jonathan' apple during cold-stored.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.139-143
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• 2014

This study was conducted to investigate the effect of cultivation period and rockwool block size on the growth and early yield of paprika transplants grown in a closed transplant production system. Paprika seeds were sown and germinated in three different size of rockwool blocks ($45{\times}40{\times}35$, $70{\times}70{\times}60$, $100{\times}100{\times}65mm$) and cultivated in a closed transplant production system for 23, 30, and 37 days after sowing. Paprika transplants were cultivated using $100{\times}100{\times}65mm$ rockwool blocks in a greenhouse following a conventional and typical production method for comparing with the growth of paprika transplants grown in a closed transplant production system. Also, we transplanted paprika transplants grown for 23, 30, and 37 days in a closed transplant production system and greenhouse to rockwool slabs and investigated fresh weight of fruits and yield 125 days after sowing. The growth of paprika transplants grown in $70{\times}70{\times}60mm$ rockwool blocks in a closed transplant production system was highest, and the quality of paprika transplant grown in a closed transplant production system was better than in a greenhouse. Rockwool block size and cultivation period in a closed transplant production system did not affect fresh weight of fruits, however, yield was largest when paprika transplants were cultivated using $70{\times}70{\times}60$ and $100{\times}100{\times}65mm$ rockwool blocks for 23 days in a closed transplant production system. These results suggest that decreasing rockwool block size and cultivation period can be strategically used to enhance transplant quality and yield of paprika, as paprika transplants were cultivated in a closed transplant production system.

• Journal of Nutrition and Health
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• v.42 no.2
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• pp.171-182
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• 2009

This study was performed to investigate socioeconomic factors relating to obesity and inadequate nutrient intake in women in low income families residing in Seoul. The subjects were 125 women (aged 41-87 y) recruited from the local health center for free health examination for low income families. The socioeconomic status such as educational level, income level, and housing condition were poor. For subjects aged less than 65 years, the prevalence of obesity was 44% based on BMI (${\geq}\;25\;kg/m^2$), 48% based on WHR (${\geq}\;0.85$), and 50% based on waist circumference (${\geq}\;80\;cm$) and for those more than 65 years, these were greater and 57%, 81%, and 79%, respectively. The main food sources of daily diet were vegetables, grains, and fruits. Energy and other nutrient intake was not adequate for all subjects and the inadequacy was more profound in the elderly, showing percentages of subjects whose intake was less than EAR were greater than 50% for all nutrients except for iron and below RI were also greater than 50% for all nutrients. The prevalence of obesity and nutrient inadequacy were not associated with socioeconomic status in subjects aged less than 65 years, however, obesity was associated with household income and nutrient inadequacy was related to education (vitamin A) and housing status (protein, phosphate, and iron) in the elderly. After adjustment for ages, in the elderly, OR for obesity (BMI ${\geq}$ 25, OR = 12.601; 95% CI = 2.338-67.911) and central obesity (WC ${\geq}$ 80 cm, OR = 4.778; 95% CI = 1.103-20.696) were greater in subjects who earned less than 500 thousand Won per month than who earned more. For inadequate nutrient intake, the OR for inadequate intake of Vitamin A (OR = 4.555; 95% CI = 1.491-13.914) was greater in subjects with no education than those educated. Subjects without her own house had greater risk for inadequate intake for protein (OR = 3.660; 95% CI = 1.118-11.981), phosphate (OR = 3.428; 95% CI = 1.157-10.158), and iron (OR = 3.765; 95% CI = 1.205-11.766) than subjects possessing her house. In elderly females in low income families, the socioeconomic status was associated with the risk for obesity (income level) and inadequate nutrient intake (education level and housing status). More attention on these groups should be given for prevention of obesity and inadequate nutrient intake.

• Journal of Animal Science and Technology
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• v.49 no.4
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• pp.471-480
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• 2007

The aim of the present study was to determine the effects of a low-energy finisher diet on feed and growth efficiencies and carcass traits of ‘high’-market weight (MW) finishing pigs and thereby to extrapolate optimal dietary energy level for the high-MW swine. A total of 160 (Yorkshire × Landrace) × Duroc-crossbred finishing gilts and barrows weighing approximately 90 kg were fed a low-energy (3,200 kcal DE/kg) diet (LE) or control (3,400 kcal) diet (CON) ad libitum in 16 pens up to 135- and 125-kg live weights, respectively, at which the animals were slaughtered and their carcasses were analyzed [2 (sex) × 2 (diet) factorial experimental design]. Average daily gain, average daily feed intake and feed efficiency did not differ between the two sex or diet groups. Backfat thickness was less (P<0.05) in LE (22.4 mm) than in CON group (24.3 mm) in gilts, but not in barrows (24.4 ± 0.4 mm). The percentage of C- & D-grade carcasses was over 90% because of the ‘over-weight’ problem in gilts, whereas in barrows, percentages of A plus B grades and C plus D grades were 79% and 21%, respectively. The yield percentage of each trimmed primal cut per total trimmed cuts (w/w) did not differ between the two sex or diet groups. Physicochemical characteristics of longissimus muscle including color (lightness and redness), pH, drip loss and chemical composition, which overally were within the range of normal carcass, also did not differ between the two sex or diet groups. In conclusion, both LE and CON are judged to be adequate for the high-MW swine during the latter finishing period. If fat deposition of a given herd of high-MW pigs needs to be suppressed by a dietary treatment, the energy content of the diet will have to be reduced to a level lower than 3,200 kcal DE/kg.

• Journal of Intelligence and Information Systems
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• v.18 no.1
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• pp.125-141
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• 2012

These days, the malicious attacks and hacks on the networked systems are dramatically increasing, and the patterns of them are changing rapidly. Consequently, it becomes more important to appropriately handle these malicious attacks and hacks, and there exist sufficient interests and demand in effective network security systems just like intrusion detection systems. Intrusion detection systems are the network security systems for detecting, identifying and responding to unauthorized or abnormal activities appropriately. Conventional intrusion detection systems have generally been designed using the experts' implicit knowledge on the network intrusions or the hackers' abnormal behaviors. However, they cannot handle new or unknown patterns of the network attacks, although they perform very well under the normal situation. As a result, recent studies on intrusion detection systems use artificial intelligence techniques, which can proactively respond to the unknown threats. For a long time, researchers have adopted and tested various kinds of artificial intelligence techniques such as artificial neural networks, decision trees, and support vector machines to detect intrusions on the network. However, most of them have just applied these techniques singularly, even though combining the techniques may lead to better detection. With this reason, we propose a new integrated model for intrusion detection. Our model is designed to combine prediction results of four different binary classification models-logistic regression (LOGIT), decision trees (DT), artificial neural networks (ANN), and support vector machines (SVM), which may be complementary to each other. As a tool for finding optimal combining weights, genetic algorithms (GA) are used. Our proposed model is designed to be built in two steps. At the first step, the optimal integration model whose prediction error (i.e. erroneous classification rate) is the least is generated. After that, in the second step, it explores the optimal classification threshold for determining intrusions, which minimizes the total misclassification cost. To calculate the total misclassification cost of intrusion detection system, we need to understand its asymmetric error cost scheme. Generally, there are two common forms of errors in intrusion detection. The first error type is the False-Positive Error (FPE). In the case of FPE, the wrong judgment on it may result in the unnecessary fixation. The second error type is the False-Negative Error (FNE) that mainly misjudges the malware of the program as normal. Compared to FPE, FNE is more fatal. Thus, total misclassification cost is more affected by FNE rather than FPE. To validate the practical applicability of our model, we applied it to the real-world dataset for network intrusion detection. The experimental dataset was collected from the IDS sensor of an official institution in Korea from January to June 2010. We collected 15,000 log data in total, and selected 10,000 samples from them by using random sampling method. Also, we compared the results from our model with the results from single techniques to confirm the superiority of the proposed model. LOGIT and DT was experimented using PASW Statistics v18.0, and ANN was experimented using Neuroshell R4.0. For SVM, LIBSVM v2.90-a freeware for training SVM classifier-was used. Empirical results showed that our proposed model based on GA outperformed all the other comparative models in detecting network intrusions from the accuracy perspective. They also showed that the proposed model outperformed all the other comparative models in the total misclassification cost perspective. Consequently, it is expected that our study may contribute to build cost-effective intelligent intrusion detection systems.

• Resources Recycling
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• v.9 no.6
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• pp.36-44
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• 2000

Fly ash was composed of the unburned carbon and mineral particles. The former was able to attach on the bubbles, while the latter was not. Therefore, it was possible to separate the unburned carbon and the mineral from fly ash using the froth flotation process. This study was carried out to evaluate the separation efficiency as a function of the ny ash particle properties in the column flotation. Separation efficiency was analyzed for various size fraction of -38 fm,38~125 fm and 1125 W, and for various fly ash samples containing 7, 11, and 20 wt% unburned carbon. For the size fractions of -38 fm containing 7 wt% unburned carbon, separation efficiency was 86ft, whereas separation efficiency was found to be 74% for the size fraction of +125$\mu\textrm{m}$ containing 20 wt% unburned carbon. The results indicated that separation efficiency increased with the decrease in the particle size and the unburned carbon content of the fly ash.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.466-473
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• 2018

An analytical method of sodium polyacrylate in processed food products was developed and monitored by using size-exclusion chromatography. GF-7M HQ column and UV/VIS detector were selected based on peak shape and linearity. Flow rate, column oven temperature, and mobile phase were selected as 0.6 mL/min, $45^{\circ}C$, and 50 mM sodium phosphate buffer of pH 9.0, respectively. Samples for analysis of sodium polyacrylate were extracted with 50 mM sodium phosphate buffer of pH 7.0 for 3 hr at $20^{\circ}C$ and 150 rpm. Analytical method validation revealed proper selectivity and calibration curve was selected in the range of 50-500 mg/L, and correlation coefficient of calibration curve was more than 0.9985. Limit of detection of sodium polyacrylate was 10.95 mg/kg and limit of quantification was 33.19 mg/kg. Accuracy and coefficient of variation for sodium polyacrylate analysis was 99.6-127.6%, 3.0-8.3% for intra-day and 94.3-121.9%, 1.3-2.6% for inter-day, respectively. Sodium polyacrylate was detected in 40 samples among monitored 125 processed food products. Detected contents were less than 0.2%, limited by the Food Additives Code. Results suggest the established size-exclusion chromatography method could be used to analyze sodium polyacrylate in processed food products.