• Membrane and Water Treatment
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• 제6권1호
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• pp.43-52
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• 2015

A small-scale electro-dialysis system was constructed for domestic use. It is composed of six compartments in which five special polystyrene ionic membranes are housed. A series of experiments on the transport of sodium and chloride ions through polystyrene membranes was performed and the effects of electric current and voltage on the pH of water were investigated. This electrodialyser could reduce the NaCl content to an acceptable level (5307 mg/L) when water containing 9945 mg/L of sodium chloride is fed to the electrodialyser. The reduction was by the action of direct current 60 mA/100 mA when a 15 V / 20 V potential is maintained across the membrane. The results showed that the pH of the treated water attained a value in the range of 7-8, with the chloride concentration of 5307 mg/L when the voltage was in the range of 20 volts. This was achieved when two of the small-scale electro-dialysers were placed in series and the solutions from the respective compartments were mixed. This is considered useful because this complies to the requirement of drinking water standard both in terms of chloride and pH. Therefore, this type electrodialyserhas the potential for domestic uses in isolated houses where potable water supply is not available.

• 한국연초학회지
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• 제23권1호
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• pp.5-11
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• 2001

Experiments were conducted to evaluated the sucker control efficiency of several suckercides and their combinations for flue-cured tobacco in Korea. In 1999, Flumetralin(Prime+, P+), Butralin(B), Fatty alcohol(FA, n-decanol 85%), pottasium salt of maleic hydrazide(MH), tank mix of MH with P+ (MH·P+), and another tank mix of MH with FA(MH·FA) were applied after topping, respectively, then sucker number and sucker dry weight were investigated on the 30th and 50th day from treatment. Sucker number and dry weight were significantly lowered by P+, B, FA and MH·P+ applications compared with those of MH and MH·FA for both investigated periods. A significant reduction in sucker number and dry weight was observed in P+, B, and MH·P+ applications. FA treatment was not so much effective in sucker control as P+. In 1999 and 2000, several suckercides and tank mixes of their combinations were applied first at button stage and second after topping, respectively, to compare the effects of sucker control on yield, price index and chemical components of cured leaves. Compared to the standard method of FA 30x at button stage followed by MH40x application after topping(FA 30x + MH 40x), sucker number and dry weight decreased by [FA 30x (or P+ 1%] or [FA 30x(or B 1.5%) + MH 60x·B 1.5%] treatments, even at reduced MH levels. But yield, price index and chemical components of cured leaves were not differed among treatments.

• Journal of Preventive Medicine and Public Health
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• 제46권4호
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• pp.155-164
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• 2013

Noncommunicable diseases (NCDs) are the most important causes of premature mortality and disability-adjusted life years in Korea. NCDs are also the main contributor to socioeconomic inequalities in mortality and life expectancy. Reduction of NCDs and NCD inequalities would result in significant improvement in healthy life expectancy and health equity in Korea. Major NCD risk factors such as dietary risks (including salt intake), alcohol consumption, cigarette smoking, and high blood pressure were found to be the leading modifiable risk factors of disability-adjusted life years in Korea, based on the 2010 Global Burden of Disease Study. Several Korean studies have shown that these risk factors play an important role in creating socioeconomic inequalities in NCD mortality and total mortality. Current international discussions on NCD policies in the United Nations and the World Health Organization would provide better opportunities for developing aggressive population-wide policy measures in Korea. Considering the paucity of population-wide policies to control major NCD risk factors in Korea, rigorous population approaches such as taxation and regulation of unhealthy commodities as well as public education and mass campaigns should be further developed in Korea.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.378-384
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• 2010

Regenerated cellulose was prepared from Buckeye wood pulp V60 via dissolution in N-methylmorpholin N-oxide (NMMO) solvent system. The effect of antioxidants such as, n-propylgallate (PG), tris(nonylphenyl) phosphite (TRIS), ethylenediamine tetraacetic acid disodium salt (EDTA), and magnesium sulfate on the properties of regenerated cellulose was studied using X-ray diffraction, copper index calculation, and viscometry. Only addition of more than 0.01% of PG into NMMO solvent was effective to avoid the reduction of the degree of polymerization(DP) of regenerated cellulose during dissolution at $110^{\circ}C$. However, the early stage(within 0.5h of dissolution process) degradation of cellulose was not prevented eventhough up to 0.5% PG was appled to hot NMMO system. In addition, to recover the expensive NMMO after cellulose regenerating process, the washing filtrate was studied using simple techniques, such as refractive index, pH, and conductivity measurements. Through conductivity measurement result, 4-time of washing was enough to remove the NMMO completely from regenerated cellulose.

• 방사성폐기물학회지
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• 제19권2호
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• pp.271-278
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• 2021

In this study, a chlorination technique for recycling Li₂ZrO₃, a reaction product of ZrO₂-assisted rinsing process, was investigated to minimize the generation of secondary radioactive pyroprocessing waste. It was found that the reaction temperature was a key parameter that determined the reaction rate and maximum conversion ratio. In the temperature range of 400-600℃, an increase in the reaction temperature resulted in a profound increase in the reaction rate. Hence, according to the experimental results, a reaction temperature of at least 450℃ was proposed to ensure a Li₂ZrO₃ conversion ratio that exceeded 80% within 8 h of the reaction time. The activation energy was found to be 102 ± 2 kJ·mol^-1·K^-1 between 450 and 500℃. The formation of LiCl and ZrO₂ as reaction products was confirmed by X-ray diffraction analysis. The experimental results obtained at various total flow rates revealed that the overall reaction rate depends on the Cl₂ mass transfer rate in the experimental condition. The results of this study prove that the chlorination technique provides a solution to minimize the amount of radioactive waste generated during the ZrO₂-assisted rinsing process.

• Journal of Dairy Science and Biotechnology
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• 제37권1호
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• pp.69-80
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• 2019

The elderly often experience difficulty while eating; this can include physical problems, such as chewing and swallowing. Furthermore, their salt intake can be high due to a diminished sense of taste and smell. This can result in a reduction in calorie intake and subsequent malnourishment. Currently, the number of food products available in the market that are targeted specifically at the older population is very low. Development of nutritional supplement-based foods for the elderly is expected to reduce these dietary problems and therefore prevent nutritional deficiencies within this population. Milk and other dairy products are excellent sources of nutrition in terms of both nutrient content and absorption rates. Dairy products have been consumed around the world for centuries, and therefore represent an excellent food source for the elderly. In addition, use of milk-derived ingredients, such as casein and calcium, will enable the development of a variety of food products and supplements targeted at this specific age group. In the future, it is expected that milk and other dairy products will be used to develop a variety of nutritious food items for the elderly in the domestic food market.

• 식품과학과 산업
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• 제50권3호
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• pp.39-50
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• 2017

In order to secure competitiveness of the home meal replacement (HMR) industry from a long-term perspective, development of packaging and processing technologies must be achieved. The development of technology that can secure freshness, nutrition, and taste but secures the shelf life is the key to the future growth of HMR. The future of HMR can be considered in terms of nutrition, environment and safety. From the nutritional point of view, it is expected that development of healthy HMR such as low-salt, low-sugar, low-fat, and high fiber and premium HMR with functional ingredient enhanced, and personalized HMR for silver, infant and patients will be done. And it is expected that development of HMR utilizing environmentally friendly food or local food, development of energy reduction and environmentally friendly disinfection technology, development of environmentally friendly packaging material, and providing information on HMR preparation using QR code and RFID from the environmental and safe point of view.

• Nuclear Engineering and Technology
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• 제54권2호
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• pp.644-652
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• 2022

During the pyroprocessing operation, various signals can be collected by process monitoring (PM). These signals are utilized to diagnose process states. In this study, feasibility of using PM for nuclear safeguards of electrorefining operation was examined based on the use of machine learning for detecting off-normal operations. The off-normal operation, in this study, is defined as co-deposition of key elements through reduction on cathode. The monitored process signal selected for PM was cathode potential. The necessary data were produced through electrodeposition experiments in a laboratory molten salt system. Model-based cathodic surface area data were also generated and used to support model development. Computer models for classification were developed using a series of recurrent neural network architectures. The concept of transfer learning was also employed by combining pre-training and fine-tuning to minimize data requirement for training. The resulting models were found to classify the normal and the off-normal operation states with a 95% accuracy. With the availability of more process data, the approach is expected to have higher reliability.

• Animal Bioscience
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• 제35권8호
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• pp.1109-1120
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• 2022

Antibiotics used to be supplemented to animal feeds as growth promoter and as an effective strategy to reduce the burden of pathogenic bacteria present in the gastro-intestinal tract. However, in-feed antibiotics also kill bacteria that may be beneficial to the animal. Secondly, unrestricted use of antibiotics enhanced the antibiotic resistance in pathogenic bacteria. To overcome above problems, scientists are taking a great deal of measures to develop alternatives of antibiotics. There is convincing evidence that probiotics could replace in-feed antibiotics in poultry production. Because they have beneficial effects on growth performance, meat quality, bone health and eggshell quality in poultry. Better immune responses, healthier intestinal microflora and morphology which help the birds to resist against disease attack were also identified with the supplementation of probiotics. Probiotics establish cross-feeding between different bacterial strains of gut ecosystem and reduce the blood cholesterol level via bile salt hydrolase activity. The action mode of probiotics was also updated according to recently published literatures, i.e antimicrobial substances generation or toxin reduction. This comprehensive review of probiotics is aimed to highlight the beneficial effects of probiotics as a potential alternative strategy to replace the antibiotics in poultry.

• 한국재료학회지
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• 제32권2호
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• pp.80-84
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• 2022

Copper nanoparticles (CuNPs) are considered of great importance due to their high catalytic and antimicrobial activities. This study focuses on the preparation and characterization of CuNPs, and on their antibacterial/antifungal activities. A copper salt (copper sulfate pentahydrate) as precursor, starch as stabilizing agent, and ascorbic acid as reducing agent were used to fabricate CuNPs. The resulting product was characterized via different techniques such as X-ray diffractrometry (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM) to confirm its characteristic properties. Employing the Scherrer formula, the mean crystallite sizes of copper (Cu) and cuprous oxide (Cu₂O) nanocrystals were found to be 29.21 and 25.33 nm, respectively, as measured from the main X-ray diffraction peaks. The functional groups present in the resulting CuNPs were confirmed by FTIR. In addition, the engineered CuNPs showed antibacterial and antifungal activity against tested pathogenic bacterial and fungal strains.