• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.2
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• pp.101-106
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• 2024

Current cold chain logistics relying on organic or eutectic materials within the 2~8℃ range as secondary fluids often face limitations in heat storage capacity, necessitating high energy consumption and large volume capacity. An effective approach to address this challenge is by incorporating polymers to enhance the heat storage capacity of eutectic materials. In this study, we investigated the impact of polyethylene glycols (PEGs) on phase change materials using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimeter (DSC), analyses of endothermic and exothermic phase change processes, and an accelerated thermal cycling test. Our findings indicate that the introduction of PEGs into the phase change materials can lead to improvements in latent heat, thermal conductivity, and 2~8℃ retention time. This enhancement is attributed to the high latent heat and thermal conductivity of the polymer, along with its ability to inhibit crystal formation in the eutectic mixture.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.8
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• pp.367-376
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• 2007

In this paper, we introduce an application-specific and adaptive power management technique for portable systems that support dynamic voltage scaling (DVS). We exploit both the idle time of multitasking systems running soft real-time tasks as well as memory- or CPU-bound code regions. Detailed power and execution time profiles guide an adaptive power manager (APM) that is linked to the operating system. A post-pass optimizer marks candidate regions for DVS by inserting calls to the APM. At runtime, the APM monitors the CPU's performance counters to dynamically determine the affinity of the each marked region. for each region, the APM computes the optimal voltage and frequency setting in terms of energy consumption and switches the CPU to that setting during the execution of the region. Idle time is exploited by monitoring system idle time and switching to the energy-wise most economical setting without prolonging execution. We show that our method is most effective for periodic workloads such as video or audio decoding. We have implemented our method in a multitasking operating system (Microsoft Windows CE) running on an Intel XScale-processor. We achieved up to 9% of total system power savings over the standard power management policy that puts the CPU in a low Power mode during idle periods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.12
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• pp.1102-1139
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• 2002

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2000 and 2001 has been done. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD technologies were widely applied for developing facilities and their systems. (2) Most of papers related with heat transfer analysis and heat exchanger shows dealt with convection, evaporation, and channel flow for the design application of heat exchanger. The numerical heat transfer simulation studies have been peformed and reported to show heat transfer characteristics. Experimental as well as numerical studies on heat exchanger were reported, while not many papers are available for the system analysis including heat exchanger. (3) A review of the recent studies on heat pump system shows that performance analysis and control of heat pump have been peformed by various simulations and experiments. The research papers on multi-type heat pump system increased significantly. The studies on heat pipe have been examined experimently for change of working characteristics and strut lure. Research on the phase change has been carried out steadily and operation strategies of encapsulated ice storage tank are reported experimentally in several papers. (4) A review of recent studies on refrigeration/air conditioning system have focused on the system performance and efficiency for new alternative refrigerants. Evaporation and condensation heat transfer characteristics are investigated for tube shapes and new alternative refrigerants. Studies on components of refrigeration/air conditioning system are carried to examine efficiency for various compressors and performance of new expansion devices. In addition to thermophysical properties of refrigerant mixtures, studies on new refrigerants are also carried out, however research works on two-phase flow seemed to be insufficient. (5) A review of the recent studies on absorption cooling system indicates that heat and mass transfer phenomena have been investigated to improve absorber performance. Various experimental data have been presented and several simulation models have been proposed. A review of the recent studies on duct and ventilation shows that ventilation indices have been proposed to quantify the ventilation performance in buildings and tunnels. Main efforts have been focused on the applications of ventilation effectiveness in practice, either numerically using computational fluid dynamics or experimentally using tracer gas techniques. (6) Based on a review of recent studies on indoor thermal environment and building service systems, research issues have mainly focused on many innovative ideas such as underfloor air-conditioning system, personal environmental modules, radiant floor cooling and etc. Also, the new approaches for minimizing energy consumption as well as improving indoor environmental conditions through predictive control of HVAC systems, various activities of building energy management and cost-benefit analysis for economic evaluation were highlighted.

• Korean Journal of Environmental Agriculture
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• v.30 no.1
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• pp.24-30
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• 2011

BACKGROUND: High input to the arable land is contributed to increasing productivity with causing the global environmental problems at the same time. Rapeseed cultivation has been forced to reassess its positive point for utilization of winter fallow field. The Objective of this study was performed to assess the environmental impact of rapeseed cultivation with double-cropping system in paddy rice on Yeonggwang district using life cycle assessment technique. METHODS AND RESULTS: For assessing each stage of rapeseed cultivation, it was collected raw data for input materials as fertilizer and pesticide and energy consumption rate by analyzing the type of agricultural machinery and working hours by 1 ton rapeseed as functional unit. Environmental impacts were evaluated by using Eco-indicator 95 method for 8 impact categories. It was estimated that 216 kg $CO_2$-eq. for greenhouse gas, 3.98E-05 kg CFC-11-eq. for ozone lazer depletion, 1.78 kg SO2-eq. for acidification, 0.28 kg $PO_4$-eq. for eutrophication, 5.23E-03 kg Pb-eq. for heavy metals, 2.51E-05 kg B(a)p-eq. for carcinogens, 1.24 kg SPM-eq. for smog and 6,460 MJ LHV for energy resource are potentially emitted to produce 1 ton rapeseed during its whole cultivation period, respectively. It was considered that 90% of these potential came from chemical fertilizer. For the sensitivity analysis, by increasing the productivity of rapeseed by 1 ton per ha, potential environmental loading was reduced at 22%. CONCLUSION(s): Fertilization affected most dominantly to the environmental burden, originated from the preuse stage, i.e. fertilizer manufacturing and transporting. It should be included and assessed an indirect emission, which is not directly emitted from agricultural activities. Recycling resource in agriculture with reducing chemical fertilizer and breeding the high productive variety might be contribute to reduce the environmental loading for the rapeseed cultivation.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.3
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• pp.400-410
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• 1999

Five experiments were conducted using finishing pigs (PIC L326 sires $\times$ C15 dams) to examine the effects of expander operating conditions on nutrient digestibility in finishing pigs. The effects of different expanding conditions (0, 11.7, 24.4, $32.5kg/cm^2$) for corn-SBM based diets (Exp. 1), wheat meddlings diet (Exp. 2), sorghum-SBM based diets (Exp. 3) and wheat-SBM based diet (Exp. 4). Exp. 5 was conducted as a $2{\times}4$ factorial arrangement and factors examined were 2 soy products (raw soybean and SBM) and 4 expanding conditions (0, 14.1, 28.1, $42.2kg/cm^2$). In experiment 1, total production rates (p>0.10) were similar among treatments. The amount of fines decreased (cubic effect, p<0.001) as cone pressure was increased from 0 to $11.7kg/cm^2$, with smaller differences as cone pressure was further increased to $35.2kg/cm^2$. Nutrient digestibilities increased (p<0.02) as the feed was subjected to higher cone pressures. Digestibilities of DM, N, and GE were maximized at $24.4kg/cm^2$ cone pressure. The DE of the diet expanded at 24.4 and $35.2kg/cm^2$ increased by 172 and 109 kcal/kg, respectively, compared to the diet processed at $0kg/cm^2$ cone pressure. In experiment 2, total production and screened pellets production rates were similar among the processing treatments (p>0.21). The amount of fines decreased (quadratic effect, p<0.03) by 9 kg/h as cone pressure was increased from 0 to $11.7kg/cm^2$. Digestibilities of DM (p<0.02), N (p<0.001), and GE (p<0.002) were increased as cone pressure was increased from 0 to $35.2kg/cm^2$. DM, N, and GE digestibility in the pigs fed the midds-based diet increased by 8, 13, and 10%, respectively, at the highest processing cone pressure compared to the diets without any cone pressure. In experiment 3, the conditioned mash moistures for the treatments were numerically similar around 15% moisture. As the expander cone pressure was increased from 0 to $11.7kg/cm^2$, energy consumption for the pellet mill decreased (quadratic effect, p<0.004) from 14.1 to 12.0 kWh/t. Dry matter and gross energy digestibility increased (cubic effects, p<0.006) as cone pressure was increased from 0 to $35.2kg/cm^2$ with the largest improvement occurring as cone pressure was increased from 0 to $11.7kg/cm^2$. Nitrogen digestibility increased (cubic effect, p<0.001) from 78.3 to 81.0% as the feed was subjected to the higher cone pressures, with N digestibility being maximized at $24.4kg/cm^2$ cone pressure. The DE of the diet increased (cubic effect, p<0.001) by 225 kcal/kg as cone pressure was increased from 0 to $11.7kg/cm^2$. In experiment 4, pellet moisture decreased and moisture loss increased as cone pressure was increased from 0 to $35.2kg/cm^2$. Also, starch gelatinization of the wheat-based diets increased from 16.8 to 49.1% as the diets were processed at 0 and $35.2kg/cm^2$ cone pressure. Nutrient digestibilities were not affected (p>0.18) by any increase in cone pressure. In experiment 5, pellet moisture decreased as cone pressure was increased 0 to $35.2kg/cm^2$. The amount of moisture loss for the diets expanded at $42.2kg/cm^2$ was 3.0 and 3.8% for the SBM and raw soybean (RB) diets, respectively. Starch gelatinization for the SBM diets were 19% greater than the RB diets. The RB diets had lower DM, N and GE digestibilities as compared to the SBM diets. The DE of the RB diets were lower (p<0.02) than the SBM diets. DM (p<0.06), N (p<0.02), and GE (p<0.001) digestibilities of the dietary treatments increased as cone pressure was increased 0 to $42.2kg/cm^2$.

• Journal of Nutrition and Health
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• v.53 no.5
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• pp.503-517
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• 2020

Purpose: This study examined the yearly trend of milk consumption and the nutritional status of subjects aged 6-18 years using the 2007-2015 Korea National Health and Nutrition Examination Survey data. Methods: Milk and dairy products were classified into plain milk, flavored milk, and dairy products (ice cream, milkshakes, cheese, and yogurt, etc.). This study compared the milk and dairy products intakes, some nutrients intakes and percent of dietary reference intakes for Koreans in the milk intake and non-milk intake groups. Results: Plain milk intake decreased with year (male, p = 0.0199; female, p < 0.0001; elementary school, p = 0.0013; high school, p = 0.0061), whereas flavored milk and dairy products intake in these subjects increased with year. In all subjects, 49.9% of subjects did not drink milk at all. The intakes of energy, protein, fat, calcium, phosphorus, and riboflavin in the milk intake group were significantly higher than those in the non-milk intake group, even after adjusting for covariates (p < 0.05). The odds ratio of the prevalence of nutritional deficiency in the non-milk intake group was 3.2 times higher than that of the milk intake group (p < 0.001), even after adjusting for covariates. The odds ratio for the prevalence of excess intake of the energy/fat was not significant with milk intake. Conclusion: The prevalence of milk intake decreased every year in the subjects. Calcium deficiency and nutritional deficiency were very high in the non-milk intake group. Efforts should be made to improve the calcium status in children and adolescents by strengthening nutrition education about the importance of milk intake.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.12
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• pp.803-812
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• 2014

This study assesses the strategy and performance of Eco-industrial Park (EIP) initiative implemented by Korea Industrial Complex Corporation (KICOX) with the support of Ministry of Trade, Industry and Energy (MOTIE), Korea since 2005 to 2013 and recommends future directions. After the concept of EIP based on industrial symbiosis (IS) is introduced, the background and implementation procedure of the EIP initiative are described. Then, economic and environmental achievement was assessed. During the project periods (2005-2013), 449 industrial symbiosis project were explored, among which 296 projects have been implemented. Among (Of these 296 projects,) them, 244 projects have been completed in which 118 projects have been commercialized which shows 48% commercialization rate of the completed projects. Through these commercialized projects, around 311.1 billion won/year of economic benefits and reduction of waste by-products of 828,113 tons/year, wastewater of 215,517 tons/year, reduction in energy consumption of 250,475 toe/year and GHG emission reduction of 1,107,189 $tCO_2/year$ were achieved. This results confirmed that EIP initiative based on industrial symbiosis can enhance eco-efficiency of industrial parks and harmonize economy and environment. However, there are obstacles like absence of interagency coordination and cooperation, laws and institutional barriers, increased demand for local governments, funding for project investment. Thus, to utilize EIP initiative as a strategic tool for competiveness and environmental management of industrial parks, it needs intergovernmental collaboration and interdisciplinary approach to lower barrier in implementation.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.428-439
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• 2020

This study was carried out to investigate the effect of PO film on the increase of crop yield and energy saving through PO and PE film greenhouse application and comparison test. As a experimental greenhouse, two single span greenhouses (1-1 W) and two double span greenhouses (1-2 W) were used. During winter season, PO film (0.15 mm outer layer, 0.10mm inner layer) was used as a covering material of greenhouse in double layers for double-span (B15) and single-span(B21), and PE film used for double-span (B15), and single-span (B23) as a control. The experimental vegetable was tomato(Solanum lycopersicum L.) cultivated in soil and the cultivar of that was 'Happiness'. That was cultivated from December 3, 2019 to April 30, 2020. The temperature at night inside the greenhouse was maintained at 15℃, and the side and roof windows were opened to maintain 23 ~ 24℃ during the day. As a result, this study showed that the yield in single-span greenhouse(B21) covered with a PO film increased 20% and that in double-span greenhouse (B16) increased by 9% compared to the greenhouse covered with a PE film (B23, B15). Fuel consumption of the single-span greenhouse (B21) with the cover of PO film was reduced by 12.4% and that of double-span greenhouse was done by 11.5% compared to that of the PE film greenhouse (B23, B15) without any difference between them in growing state.

• Journal of Nutrition and Health
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• v.47 no.4
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• pp.277-286
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• 2014

Purpose: The aim of this study was to examine the characteristics of nutrition-related knowledge, dietary habits, and nutrient intakes of alcoholic patients and how nutrition education affects these nutritional behaviors. Methods: Subjects included 37 adult male alcoholic patients who were hospitalized. The nutrition education program consisted of five lessons over a five-week period. An each 80-minute nutrition education program per week was implemented for the alcoholic patients over a five-week period. Both before and after the implementation of nutrition education, their nutrition-related knowledge and dietary habits were assessed and nutrient intakes were investigated. Results: The subjects showed drinking habits of considerably high frequency, a large quantity of alcohol consumption, and preference for soju (a liquor) over beer. They had proper weight, height, and BMI, and came from relatively poor socioeconomic backgrounds with a low-level of self-rated health status and a comparatively high rate of suffering from disease. Mean score of their nutrition-related knowledge and dietary habits was quite low. They consumed less energy, dietary fiber, vitamin C, thiamin, riboflavin, folic acid, Ca, and K, but more Na compared to each Dietary Reference Intake (DRI). After implementing the nutrition education, mean score of nutrition-related knowledge and dietary habits showed significant improvement. In addition, the meeting rate of each DRI of several nutrients was increased significantly, including energy, carbohydrate, dietary fiber, vitamins A, C, and $B_6$, thiamin, riboflavin, niacin, pyridoxine, folic acid, Ca, P, K, Fe, and Zn, while that of Na decreased. Conclusion: The findings of this study indicate that alcoholic patients had various nutritional problems, such as lack of nutrition-related knowledge, bad dietary habits, and insufficient nutrient intakes, however, these problems can be positively modified by implementation of a relatively short-term nutrition education program.

• Korean Journal of Community Nutrition
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• v.19 no.6
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• pp.527-536
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• 2014

Objectives: The aim of this study was to assess how nutrient intakes are related to risk factors for metabolic syndrome according to dietary patterns in the middle-aged adults. Methods: The subjects (n = 187; 47 men, 140 women) consisted of middle-aged adults over 30 years old in Ilsan area. The metabolic syndrome was diagnosed according to the data collected from each subject, including anthropometric measurements and blood analyses. The dietary patterns were derived from the average of two-day dietary intake data. Results: Factor analysis identified three major dietary patterns which were "Meats and alcohol", "Mixed grains, vegetables and fruits", and "Rice, Kimchi and fish & shellfish". The daily intakes of energy, protein, and sodium increased across quartiles of "Meats and alcohol" pattern scores (p < 0.05), whereas the intakes of carbohydrates, potassium, calcium, and fiber increased across quartiles of "Mixed grains, vegetables and fruits" pattern scores (p < 0.001). The "Meats and alcohol" pattern scores were positively correlated with protein and sodium intakes but inversely correlated with carbohydrates, fiber and potassium intakes which were adjusted for age, sex and energy (p < 0.05). The highest quartile pattern score of "Meats and alcohol" pattern had elevated odds ratio of abdominal obesity and metabolic syndrome (p < 0.05). The risk of hypertriglyceridemia decreased in the highest quartile of "Mixed grains, vegetables and fruits" pattern (OR 0.35, 95% CI 0.12-1.00). Conclusions: Our results suggested that reducing the consumption of meat and alcohol along with increasing fruits, vegetables and mixed grains would be helpful for preventing the metabolic syndrome and chronic diseases.