• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.703-709
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• 2013

Ozonation was performed under various experimental conditions that $Al_2O_3$ catalysts dosage and temperature for removal of DMP in laboratory scale batch reactor. Flow rate of ozone $1.0Lmin^{-1}$ and ozone concentration of $300{\pm}10mgL^{-1}$ were maintained constantly, and the pH, $COD_{Cr}$ and TOC was measured in 10 min intervals during the 60 min at oxidation processes. As a result, the presence of the $Al_2O_3$ than only ozonation increased the removal efficiency of both $COD_{Cr}$ and TOC in solution. The pseudo first-order rate constants for the elimination of $COD_{Cr}$ and TOC were $3.65{\times}10^{-4}sec^{-1}$, $2.52{\times}10^{-4}sec^{-1}$, and activation energy was $0.75kcal{\cdot}mol^{-1}$ and $0.70kcal{\cdot}mol^{-1}$ at $20^{\circ}C$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.867-873
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• 2007

Thermal degradation characteristics of polypropylene and polystyrene have been studied in the thermogravimetric(TG) reactor and batch-type microreactor. The dynamic thermogravimetric curve of TG provided a valuable information about pyrolysis temperature. It was found that PS was thermally degraded at lower temperature of $30{\sim}50^{\circ}C$ than PP. It was found that the yield and molecular weight of liquid product in the microreactor were decreased with the increase of reaction temperature and time in the case of PP. The production of styrene monomer was significantly increased by the promotion of depolymerization with the increase of temperature and time. The chain-end scission rate parameters were determined to be 50.0 kcal/mole of PP, 45.2 kcal/mole of PS by the Arrhenius plot.

• Resources Recycling
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• v.10 no.4
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• pp.34-41
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• 2001

A research was performed to evaluate a use of shredder residue to currently dispose of at landfills. Laboratory analyses were conducted to determine especially the fuel characteristics of shredder residue. For this aim, shredder residue was classified by the particle size as well as by the type of material and the content of Cl, S, ash, and calorific value were determined. Due to the chlorinated plastic content of shredder residue, mean concentration of Cl was found to exceed 4wt% except one sample while that of S was ranged from 0.25 to 0.39 wt%. As far as calorific value was concemed, plastic was observed to be more than 10,000 kcal/kg while wood/paper and fiber accounted for approximately 4,000 kcal/kg. Shredder residue was found to contain varying trace amounts of metal elements, including Fe of 6∼8.5 wt%. Hg and Cr(VI) were not detected, however, while Cd was contained as small as 0.0004-0.0009 wt%.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.28-33
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• 2015

In this study, a dual fuel engine fueled with natural gas and diesel was tested to investigate the effects of heating value variation of CNG fuel. CNG substitution rate which is defined as the ratio of CNG and diesel supplied in a heating value basis was fixed at 80%. The higher heating value was varied from $10,400kcal/Nm^3$ to $9,400kcal/Nm^3$ by mixing nitrogen gas with pure CNG and diesel fuel was injected at a fixed injection timing. The engine test results showed that thermal efficiency and power output were decreased as the heating value of mixed CNG fuel was decreased. And the peak cylinder pressure was also decreased but the ignition delay time and the combustion duration and timing were almost same.

• Journal of the Korean Society of Food Culture
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• v.36 no.6
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• pp.583-594
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• 2021

This study examined the nutrient intake of Korean adults by considering the lunch type, categorized as home meals (HM), eating out (EO), and institutional meals (IM). Data was obtained from the 2019 Korea National Health and Nutrition Examination Survey (KNHANES). Totally, 3,786 adults (1,643 men, and 2,143 women) aged between 19-64 years were included in the study. Subjects with daily energy intake of less than 500 kcal or over 5,000 kcal, and those who skipped lunch, were excluded. The percentage of subjects in the HM, EO, and IM were 31.9, 53.6, and 14.4%, respectively. The daily energy intakes of the HM, EO, and IM groups were determined to be 2,185, 2,360, and 2,339 kcal, respectively, in men, and 1,622, 1,731, and 1,741 kcal, respectively, in women. Among the three groups, men in the EO group had more intake of fat, saturated fat, cholesterol, sodium, and riboflavin, and less dietary fiber, and whereas women consumed more fat and less dietary fiber and potassium. In the IM group, the men consumed more dietary fiber, potassium, and thiamine, whereas consumption of carbohydrate, unsaturated fatty acid, sodium, potassium, and thiamine was more in women. Energy contributions of carbohydrate, protein, and fat were all within the AMDR (acceptable macronutrient distribution ranges) for all lunch types, except for the percent of energy provided from saturated fat in EO (7.4% in men, and 8.2% in women). Our results indicate that the dietary habit of frequently eating out increases the fat intake, thereby resulting in increased health risks for adults. Thus, implementation of a nutritional education program to encourage balanced dietary habits is required to improve the nutritional status of individuals eating out.

• Food Science and Industry
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• v.52 no.4
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• pp.375-386
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• 2019

Carbohydrates play an important role in not only providing the body with calories but also giving taste and texture in foods. Recently, there is a growing interest in low-calorie carbohydrate materials due to obesity and the resulting diseases caused by excessive intake of calories. Polydextrose and sugar alcohols have calories of 2.0 kcal/g and 2.4 kcal/g, respectively. In addition to being a low-calorie material, polydextrose can be widely used as a dietary fiber source, thereby reducing calories and supplementing fiber. Sugar alcohols have sweetness comparable to a table sugar but they are not calculated as a sugar, so it can meet the government's sugar reduction policy. Also, polydextrose and sugar alcohols are not easily decomposed by heat and acid, and thus can be used without being affected by food manufacturing processes.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.45-50
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• 2022

The aim of this study is to evaluate the effects of supplementation of low-energy diets with PROSOL^® (sodium stearoyl-2-lactylate) as an emulsifier on the growth performance and nutrient digestibility of growing pigs. A total of 120 crossbred ([Landrace × Yorkshire] × Duroc) growing pigs with an average initial body weight of 23.80 ± 4.87 kg were used in a 56-day feeding trial and were sorted into three dietary treatments. Each treatment utilized eight replications with five pigs per pen. The dietary treatments were as follows: PC (high, net energy diet [NE] = 2,488 kcal·kg^-1 [weeks 1 to 4] and NE = 2,477 kcal·kg^-1 [weeks 5 to 8]); NC (low, NE = 2,472 kcal·kg^-1 [weeks 1 to 4] and NE = 2,468 kcal·kg^-1 [weeks 5 to 8]); NC1 (NC + 0.05% PROSOL^® emulsifier). Growth performance outcomes were measured at the initial point and at weeks 4 and 8 while nutrient digestibility parameters were measured at weeks 4 and 8. From weeks 1 - 8, body weight and the average daily gain of the NC1 group pigs showed significant increases (p < 0.05) compared to those of the PC and NC treatment groups. At the end of the trail, pigs fed a diet containing low net energy with 0.05% of the emulsifier showed reduced feed conversion ratio (FCR) levels. However, the average daily feed intake and nutrient digestibility of dry matter and nitrogen remained unaffected throughout the experiment. In summary, the addition of a low-net-energy diet with 0.05% sodium stearoyl-2-lactylate as an emulsifier enhanced the body weight and daily gain with no adverse effects on nutrient digestibility in growing pigs.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.2
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• pp.53-61
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• 2023

Most of the sewage sludge is organic waste containing a large amount of organic substances decomposable by microorganisms by biological treatment. As for existing sewage sludge treatment methods, reduction and fuel conversion are being carried out using technologies such as drying, incineration, torrefaction, carbonization. However, the disadvantage of high energy consumption has been pointed out as latent heat of 539 kcal/kg is consumed based on drying. Therefore, in this study, we intend to produce solid fuel through hydrothermal carbonization(HTC), which is a thermochemical treatment. To evaluate the value of solid fuel, the characteristics of carbonization and fuel ratio were analyzed. As a result, as the hydrothermal carbonization reaction temperature increased, the lower heating value also increased by about 500 kcal/kg due to the increase in the degree of carbonization. H/C, O/C, ratio showed a decreasing trend from 1.78, 0.46 to 1.57, 0.32. When the ratio of ash to combustible content (fixed carbon + volatile) of dry sludge was 0.25 or more, it was derived that the degree of carbonization and calorific value did not increase even when hydrothermal carbonization was performed.

• Korean Journal of Exercise Nutrition
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• v.13 no.2
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• pp.123-130
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• 2009

The purpose of this study was to provide the basic information on nutritional condition for improving performance of the national junior rowing team players(male n=17, female n=14). To attain this purpose, their body composition and energy intake situations were investigated during their three-week winter training camp. Measurement of body composition measured by the interval, and two days, and dietary intake in this study to investigate the type and amount of food, the researchers measured directly, and then refer to the record subjects to investigate the dietary intake and the adoption of a Weighing Method. The result is as follows. During training, body composition due to the high intensity training to maintain a properly balanced diet is the consumption of energy, weight and body composition has a positive influence. The male players' average energy intake is 5,951.6 kcal(72.6 kcal/kgBW, 150%), the rate of the three main nutrients, carbohydrate, fat, protein, is 72.6 : 8.7 : 18.7 respectively. For the female, the average energy intake is 3,685.6 kcal(51.8 kcal/kgBW, 121%), and the rate of the three main nutrients is 76.3 : 8.5 : 15.2. Both of male and female were taken sufficient Vitamin, mineral and other nutrient according to %RI(recommended intake). Based on the results of a survey of elite athletes and nutrition management and the systematic introduction and review of the program in conjunction with a professional nutritionist would need, and can also be applied to expand the school to the scene, the reality of the program review and development of qualified need.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.4
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• pp.5-11
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• 2023

This study was conducted to improve energy efficiency and problems such as clumping and fouling in the glue zone that occur in the moisture content range of 40 to 60% when sewage dehydration residue is directly fed into the dryer. The temperature of the hot air is low at 270~300℃, and the paddle-type flotation method and dehydrated residue are applied to the circulated heat storage media to increase the contact area with the hot air, thereby reducing energy recovery and gas emissions. The water content of the dried residue is 2.7. ~7 .5%, the heat of evaporation of moisture was 608.0~690.6 kcal/kg·H₂O, which confirmed an energy saving effect of about 8.8% compared to the heat of evaporation of moisture of 714.5 kcal/kg·H₂O when no heat storage media was used.