• The Korean Journal of Ecology
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• v.26 no.6
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• pp.313-319
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• 2003

Dry weight loss and nutrient release from leaf litter for six tree species were studied using litter bag methods. The litter bags were incubated for f6 months on the forest floor in temperate deciduous forest in Mt. Cheonma, located at the middle part of Korean Peninsula. The changes in nutrient content and the rate of dry weight loss in leaf litter varied with litter types. The litter of Pinus densiflora showed the lowest rate of mass loss (k=0.33), nitrogen concentration (0.89%) and ash concentration (2.50%), while showed the highest C/N ratio (63.40). On the other hand, the litter of Acer pseudo-sieboldianum showed the fastest rate of mass loss (k=0.82), the highest nitrogen concentration (1.11%), and the lowest C/N ratio (49.40). During the decomposition, nitrogen, phosphorus and calcium in the leaf litters showed relatively slow decreasing pattern compared to other elements (carbon, potassium, magnesium, manganese and sodium), but potassium and sodium decreased at early stage of the decomposition for all leaf litters. Differences in annual decomposition rates of litter among species were consistent with the particular chemical characteristics of their leaf litters. The initial concentration of nitrogen was positively correlated with litter decomposition rate for six species, while litter decomposition rate of six species was negatively correlated with C:N ratio of initial leaf litters.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.5
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• pp.441-445
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• 2017

This study aimed to investigate growth rate and nutrient consumption of Chlorella vulgaris according to different light irradiation interval. Applied light irradiation intervals were 12 hr, 4 hr, 1 hr, and 1 min. The light source was flexible LED(Blue:Red=1:1), light intensity was 200 PPFD and Light/Dark cycle was 1:1. As a result, growth rate and nutrient removal efficiencies showed no significant differences depending on the light irradiation interval. Considering the reproduction characteristics of applied microalgae cultures of this study, this is thought to be one of the possible reasons of above results. Because Chlorella vulgaris performs an asexual reproduction and it is known that there is no significant relationship between light irradiation interval and growth rate, including nutrient consumption in case of asexual reproduction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.268-274
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• 2010

The aim of our study was to investigate the interactive effects of container size and nutrient supply on plant growth, chlorophyll synthesis, transpiration, $CO_2$ assimilation, water use efficiency (WUE), and nutrient uptake of vinca plant (Catharanthus roseus). A complete experiment utilizing four concentrations of fertilizer and three volumes of containers was conducted. As the container size was increased, the plant height, leaf area, and dry weight of vinca significantly increased regardless of fertilizer level. The leaf area and dry weight of vinca were highly sensitive to the container size. However, the chlorophyll contents of vinca 20 days after the transplant significantly increased with decreasing container sizes and increasing fertilizer concentrations. Significant differences in transpiration and $CO_2$ assimilation occurred with the use of differentfertilizer solutions, but the highest values for transpiration and $CO_2$ assimilation were in plants grown in the 15 cm-diameter containers. The highest water use efficiency was observed in the plants grown in 10 cm-containers with 4 dS/m of fertilizer, and there were no significant differences in WUE values among container sizes with fertilizer concentrations of 0, 1, or 2 dS/m. No significant difference in nutrient uptake was observed among the fertilizer levels or among the container sizes. However, at a fertilizer concentration of 4 dS/m, the uptake of several nutrients, including N, P, K, Ca, Mg, B and Fe, was higher in small containers than in larger ones.

• Korean Journal of Community Nutrition
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• v.8 no.5
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• pp.689-698
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• 2003

The purpose of this study was to evaluate the relationship between the diversity of food intake and nutrient intake among Korean college students participating in a nutrition education class via the internet. The subjects were 796 college students throughout South Korea (278 males, 518 females). A 3 days dietary recall survey was conducted and results were analyzed using the Computer-aided Nutritional Analysis Program. Dietary variety was assessed by DDS (dietary diversity score), MBS (meal balance score), and DVS (dietary variety score). Dietary quality was assessed by NAR (nutrient adequacy ratio), and MAR (mean adequacy ratio). As the DDS, MBS and DVS increased, the NAR and MAR improved. The subjects with a DDS of above 4 or a MBS of above 10 or a DVS of above 11 met two-thirds of the Korean recommended dietary allowance for most nutrients. The DDS, MBS and DVS correlated positively and significantly with the NAR and MAR. Associations between the NAR and high levels of DVS were more positive than those between the NAR and the DDS. Based on these results, the food intake of these subjects was not adequate. Specially, the dietary intake of calcium and iron were not adequate. Therefore, dietary guidelines should be made considering nutritional characteristics so as to improve the intake from all of the major food groups and provide a variety of foods in their diets.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.3
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• pp.113-121
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• 1994

Since it is difficult to expect the normal production of plants in greenhouses during hot summer season in Korea, certain provisions on the control of extreme environmental factors in summer should be considered for the year-round cultivation in greenhouses. This study was carried out to find a method to suppress the temperature rising of nutrient solution by cooling, which is able to contribute to the improvement of the plant growth environment in hydroponic greenhouse during hot summer season. A mechanical cooling system using the counter flow type with double pipe was developed for cooling the nutrient solution efficiently. Also the heat transfer characteristics of the system was analysed experimentally and theoretically, and compared with the existing cooling systems of nutrient solution. The cooling capacities of three different Systems, which used polyethylene tube in solution tank, stainless tube in solution tank, and the counter flow type with double pipe, were evaluated. The performance of each cooling system was about 41 %, 70% and 81 % of design cooling load in hydroponic greenhouse of 1 ,000m$^2$ on the conditions that the flow rate of ground water was 2m$^3$/hr and the temperature difference between two liquids was 10 ˚C According to the results analysed as above, the cooling system was found to have a satisfactory cooling capability for regions where ground water supply is available. Fer the other regions where ground water supply is restricted, more efficient cooling System should be developed.

• The Korean Journal of Food & Health Convergence
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• v.8 no.2
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• pp.7-13
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• 2022

The purpose of this study was to compare the nutrient intake of elderly according to their cohabitation status and determine its effects on the prevalence of anemia. Data from the KNHANES were used for this study, including raw data on socioeconomic characteristics, nutrient intake, health status, and clinical laboratory findings. Study subjects aged 60 to 80 years were retrieved and analyzed. As a result, the prevalence of anemia was 12.0% (men, 11.6%; women, 12.3%). The prevalence rate increased with age, and odds ratio [OR] of anemia among those aged 75 to 80 years was 4.16 times higher in men (OR=4.16, 95% confidence interval [CI]=2.48-6.97) and 2.77 times higher in women (OR=2.77, 95% CI=1.86-4.14) compared to 60~64 years old. Socioeconomic factors (area of residence, education level, household income), including cohabitation Status (living alone VS living with other family members), and health behaviors (high-risk drinking, smoking, aerobic exercise) did not significantly effect on anemia. In addition, other than protein intake for men, nutrient intake did not have a significant effect on the prevalence rate of anemia. Hypertension, diabetes, and cancer significantly increased the risk of anemia. In Korea, the influencing factors of elderly anemia change over time, so periodic follow-up studies are needed.

• Journal of the Korean Dietetic Association
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• v.22 no.2
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• pp.88-105
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• 2016

This study investigated anthropometric and biochemical characteristics, food and nutrient intakes, and changes in body mass index (BMI) of Korean middle age men (40~49 yrs). Data on BMI, anthropometric (height, weight, waist circumference, body mass index, blood pressure), and biochemical (total cholesterol, HDL-cholesterol, LDL-cholesterol, triglyceride, hemoglobin, GOT, GPT) characteristics, food and nutrients intakes, nutrient density, and index of nutrient quality were obtained from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES, 2001, 2005, 2011). Subjects were divided into three groups by year. Weight, BMI, and hemoglobin increased significantly by year. All anthropometric factors except height showed a positive relation with BMI by year. Consumption of barley, chinese noodle, confections, soybean milk, egg, ice cream, pizza, fried foods, banana, coffee, and raw rice wine increased significantly by year. Intake ratios of nutrients except water and fiber were over 100% of KDRI generally. INQ according to intakes of protein, calcium, phosphorus, iron, vitamin A, thiamine, riboflavin, and niacin per 1,000 kcal increased significantly by year. Distribution of BMI status of subjects showed a significant difference by exercise. The findings of the present study show that BMI of subjects increased by year, and intakes of all nutrients except calcium and riboflavin showed aspects of overnutrition by year. Intakes of fruits decreased while intakes of raw rice wine and coffee increased by year. Therefore, practical and systematic nutrition programs are required to maintain optimum BMI and appropriate intakes of nutrients to maintain a desirable lifestyle and improve dietary life.

• Korean Journal of Community Nutrition
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• v.6 no.2
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• pp.250-258
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• 2001

Five representative local foods of Cheollabuk-do Province such as chuotang, ochuk, baekhapchuk, dasulgitang and minmulgokimaeuntang were subjected to recipe standardization and nutrient analysis. To derive a standard recipe, first a test recipe was prepared with the consideration of information obtained from literature survey, personal interview and survey of restaurant recipe. This test recipe was modified three times after sensory evaluation. Then the modified test recipe was accepted as the standard recipe when all characteristics of food was assessed over 5 points and the percentage of judges who gave a score over five exceeded 70% in seven-point hedonic scale. Actually, all characteristics of each food were judged as "satisfactory". Nutrient analysis was performed in food cooked according to the decided standard recipe. In general, it appeared that energy content was rather low. However protein contents in chuotang, ochuk and minmulgokimaeuntang were higher than the recommended value per meal. Vitamin A, vitamin C, vitamin B$_1$, vitamin B, niacin, calcium, phosphorus and iron were rich in chwotang and minmulgokimaeuntag. Onhuk contains plenty of vitamin C, vitamin B$_1$, vitamin B$_2$and the contents of vitamin A, vitamin B$_1$, and niacin in baekhapapchuk were over the recommended values per meal. The foods contained large percentage of aspartic acid and glutamic acid, and major essential amino acids appeared to be leucine and lysine. On the other hand, major fatty acids were oleic acid, linoleic acid and plamitic acid. Among them the content of oleic acid was the highest in chuotang, ochuk and baekhapchuk, whereas linoleic acid and palmitic acid were the most rich fatty acids in baekhapchuk and dasulgitang respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1150-1157
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• 2004

This experiment was conducted to investigate effects of phase feeding and sugar beet pulp (SBP) on growth performance, nutrient digestibility, nitrogen excretion, blood urea nitrogen (BUN) concentration and carcass characteristics in finishing pigs. A total of 128 pigs were allotted at 53.9 kg BW to 8 replicates in a 2$\times$2 factorial arrangement in a randomized complete block (RCB) design. The first factor was phase feeding (2 or 3 phase feeding) and SBP (SBP: 0% or 10%) was the second factor. Ten percent SBP supplement groups showed lower average daily feed intake (ADFI) than 0% SBP supplement groups (p<0.05). However, there were no significant difference in average daily gain (ADG) and feed:gain ratio among treatments during overall experimental period. Nutrient digestibility was not affected by phase feeding or SBP supplementation. Urinary nitrogen excretion in 10% SBP supplement group was lower than that in 0% SBP supplement group (p<0.05) and total nitrogen excretion was lower in SBP supplement group than in the group without SBP. Urinary and total nitrogen were numerically decreased in three phase feeding compared to two phase feeding. The BUN concentration in three phase feeding groups was lower than two phase feeding groups at 47 and 63 day (p<0.05). Consequently, results of this experiment demonstrated that three phase feeding was more acceptable than two phase feeding for finishing pigs. And sugar beet pulp could be supplemented in finishing pig diet for decreasing urinary nitrogen excretion without retardation in growth performance of pigs.

• Korean Journal of Agricultural Science
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• v.44 no.2
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• pp.235-243
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• 2017

A total of 112 crossbred pigs [(Yorkshire ${\times}$ Landrace) ${\times}$ Duroc] with an average body weight (BW) of $27.98{\pm}1.28kg$ were used to evaluate the effects of replacing soybean meal (SBM) with rapeseed meal (RSM) as a source of protein on growth performance, nutrient digestibility, blood characteristics, and fecal noxious gas emission in growing pigs. The pigs were blocked and stratified based on BW into one of four dietary treatments in a 6-week trial. Each treatment consisted of 7 replicate pens with 4 pigs per pen (2 barrows and 2 gilts). Treatments were 1) maize-SBM based diet, 2) diet containing 2% RSM, 3) diet containing 4% RSM, and 4) diet containing 6% RSM. Supplementation with RSM resulted in no differences in growth performance, nutrient digestibility, and noxious gas emission, as compared with SBM supplementation during the experimental period (p > 0.05). Pigs fed with increased dietary RSM (0, 2, 4, and 6% of feed) had linear decreases in average daily gain (ADG) (p = 0.010) and nitrogen digestibility (p = 0.036) and a linear increase in blood creatinine concentration. In conclusion, RSM fed pigs had no detrimental effects on their growth performance, nutrient digestibility, blood characteristics, and fecal noxious gas emissions, as compared with SBM fed pigs. Thus, RSM is a good alternative to SBM as a protein source in growing pigs' diets.