• Food Science and Preservation
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• v.15 no.3
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• pp.461-468
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• 2008

To obtain basic da1a on the preparation of Cudrania tricuspidata leaves tea, the quality and anti-oxidative characteristics of dried raw leaves (RT), pan-fired leaves tea (PT) and fermented leaves tea (FT) were investigated. General characteristics of RT, PT and FT, respectively, were: moisture content 18.47, 6.23 and 8.50%; crude protein content 17.77, 20.46 and 19.13%; and carbohydrate content 54.42, 62.52 and 61.96%. The crude lipid and ash contents were in the range 0.05 - 0.07% and 9.27 -10.74% respectively; the water soluble solid content was in the order FT > PT > RT and ranged from 23.10 - 37.38%; there were no significant differences in the total polyphenol content (815.24 - 835.16 mg%). Although $L^*$ values of PT (20.94) and FT (20.85) were lower than those of RT (34.71), the $a^*$ value in PT and the $b^*$ value in FT were highest. In all ethanol extracts the reducing power, electron-donating ability and superoxide dismutase (SOD)-like activity increased in a concentration-dependent manner. Furthermore, the activity in FT was higher than in PT or RT. The total free amino-acid content was higher in FT (1429.93 mg%) than RT (1108.94 mg%) or PT (833.13 mg%). The major amino acids were L-asparagine and L-valine in RT, L-cysteine and L-glutamic acid in PT and L-proline in FT. In a sensory evaluation of PT and FT, bitter and astringent tastes were decreased relative to RT, while sweet and savory tastes, flavor, color and overall acceptability were increased. These results indicate that FT bas a higher antioxidant effect and free-amino-acid content than PT, while the sensory quality of FT is similar to that of PT.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.434-451
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• 2017

For this study, groundwater samples for 3 years from 2011 through 2013 were collected at 106 groundwater monitoring site in Korea. These groundwater samples were analyzed for 13 pesticides such as cabofuran, pentachlorobenzene, hexachlorobenzene, simazine, atrazine, lindane (gamma-HCH), alachlor, heptachlor, chlordane (total), endosulfan (1, 2), dieldrin, endrin, 4,4-DDT. The objectives of this study were to determine the detection frequency and their concentrations of 13 pesticides and evaluate the health risk level considering ingestion, inhalation, and skin contact using concentrations of 13 pesticides in groundwater samples. An analysis was used for the simultaneous determination for 13 pesticides using GC-MS. GC-MS was performed on HP-5ms, using helium ($1ml\;min^{-1}$) as carrier gas. The average recoveries of the pesticides were from 92.8% to 120.8%. The limits of detection (LODs) were between $0.004{\mu}g\;L^{-1}$ and $0.118{\mu}g\;L^{-1}$ and the limits of quantification (LOQs) were between $0.012{\mu}g\;L^{-1}$ and $0.354{\mu}g\;L^{-1}$. 106 groundwater wells were selected. 54 wells were from well to monitor background groundwater quality and 52 wells were from well to monitor groundwater quality in industrial or contamination source area. Eight pesticides including pentachlorobenzene, lindane (Gamma-HCH), heptachlor, chlordane (total), Endosulfan (1, 2), dieldrin, endrin, and 4,4-DDT were not detected in groundwater samples. The detection frequency for hexachlorobenzene, alachlor, carbofuran and simazine was 23.4%, 11.4%, 7.3%, and 1.0%, respectively. Atrazine was detected once in 2011. The average concentrations were $0.00423{\mu}g\;L^{-1}$ for carbofuran, $0.000243{\mu}g\;L^{-1}$ for alachlor, $0.00015{\mu}g\;L^{-1}$ for simazine, and $0.00001{\mu}g\;L^{-1}$ for hexachlorobenzene. The detection frequency of hexachlorobenzene was high, but the average concentration was low. In the contaminated groundwater, the detection frequency for hexachlorobenzene, alachlor, carbofuran, simazine and atrazine was 26.1%, 21.3%, 7.1%, 1.9% and 0.3%, respectively. In the uncontaminated groundwater, detection frequency for hexachlorobenzene, carbofuran and alachlor were 20.2%, 7.5%, and 1.9% respectively. Simazine and atrazine were not detected at uncontaminated groundwater wells. According to the purpose of groundwater use, atrazine was detected for agricultural groundwater use. Hexachlorobenzene showed high detection frequency at agricultural groundwater use area where the animal feeding area and golf course area were located. Alachlor showed more than 50% detection frequency at cropping area, pollution concern river area, and golf course area. Atrazine was detected in agricultural water use area. By land use, the maximum detection frequency of alachlor was found near an orchard. For human risk assessment, the cancer risk for the 5 pesticides was between $10^{-7}$ and $10^{-10}$, while the non-cancer risk (HQ value) was between $10^{-4}$ and $10^{-6}$. For conclusion, these monitoring study needs to continue because of the possibility of groundwater contamination based on various purpose of groundwater use.

• Management & Information Systems Review
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• v.36 no.5
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• pp.45-60
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• 2017

This study aims to elucidate the key improvements through the current state of customer support for smart home services based on the Internet of things and the evaluation of user's usage. Smart home services typically provide a wide range of value in terms of security, safety, manageability (electricity and water use), convenience, and remote management accessibility. In this study, we analyzed the current state of smart home service based on Internet of Samsung, SKT and LG U + companies in Korea. However, since LG U+ is the only company providing user reviews, there is a limit to generalization, but we are trying to figure out whether the customer value is conveyed properly or not, and in which part the customer support is focused to support the service. As a result of analyzing the results of the study, we found that the smart home service is commercialized and marketed in various forms. However, it is questionable whether the technological level and user satisfaction level are sufficiently satisfied. The results of this study are as follows. First, although each company provides usage guidance, they still ask many questions about joining products and using products. Second, there are many defects in the product itself, and it is found that the companies are not satisfied with the overall response. Third, the three companies are focusing on switches, outlets, sensors, and lamps. This is an individual intelligent product rather than an interlocking or linking level, and it can be seen that there are many parts that are not compatible with the concept of the original Internet of things. In conclusion, this study shows that there are still many areas to improve on the level of customer service provision of smart home service, in particular, the ease of use is low and the quality of products is not reliable. We would like to present the improvement of this in detail through this study and reflect the companies that provide it and the service providers.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.94-131
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• 2007

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, 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 and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.41.2-41
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• 1981

Tonsillectomy and adenoidectomy are the most common operations in the ENT field. Recent emphasis on careful selection of patients for these procedures derives from concern for complications of surgery, as well as the immunologic and anatomic functions of tonsils and adenoids. Adenoidectomy can relieve nasopharyngeal airway obstruction caused by enlarge adenoids, and can prevent complications such as heart failure and recurrent or chronic otitis media. We researched 117 cases of tonsilloadenoidectomy patients and 266 patients having routine examination from March, 1979 to February, 1981, and described the A/N ratio derived from linear measurements of lateral radiographs of the nasopharynx. The results of Impedance Audiometry and X-ray films from 117 cases of T&A patients were compared: 1) The average A/N ratio by age groups for 266 cases of normal children showed: 0.508 for age group, 0 to 3 years old, 0.533 for age group, 4 to 6 years old, 0.524 for age group, 7 to 9 years old, 0.519 for age group, 10 to 12 years old, 0.507 for age group, 13 to 15 years old, 0.481 for age group over 15 years old. The peak value lies in the age group of 4 to 6 years old. The sex difference of A/N ratio was not significant. 2) The average A/N ratio by age groups from 117 cases of T&A patients showed: 0.709 for age group, 0 to 3 years old, 0.733 for age group, 4 to 6 years old, 0.693 for age group, 7 to 9 years old, 0.707 for age group, 10 to 12 years old, 0.620 for age group, 13 to 15 years old, 0.756 for age group over 15 years old. 3) Among the 117 cases of T&A patients, the average A/N ratio for 57 cases in normal tympanogram was 0.688 and the average A/N ratio for 60 cases in abnormal tympanogram was 0.705. 4) Among 57 cases in abnormal tympanogram: 6 cases (10.5%) showed 0.40-0.59 of A/N ratio, 44 cases (77.2%) showed 0.60-0.79 of A/N ratio, and 7 cases (12.3%) showed 0.80-0.99 of A/N ratio. 5) Among 117 cases of T&A patients, 3 of 15 cases showing A/N ratio under 0.6, and 67 of 102 cases showing A/N ratio over 0.6, had paranasal sinusitis.

• Food Science and Preservation
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• v.23 no.7
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• pp.995-1003
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• 2016

Ulmus pumila L. bark underwent distilled water extraction under three temperature condition ($4^{\circ}C$, room temperature, or $80^{\circ}C$) and two extraction times (1, or 5 min) in order to develop a functional beverage products. Changes in yield, pH, color, total phenolic (TP) content, tannin content and antioxidant activity of the aqueous extracts were evaluated for each extraction temperature and duration. Extraction conditions did not affect yield or pH value of the extracts; however CIE $b^*$ values were high in extracts prepared under high extraction temperature ($80^{\circ}C$) and long extraction duration (5 min) conditions. Both extraction temperature and duration affected the TP and tannin contents of the extracts; however, all extraction conditions resulted in ${\geq}450\;mg\;GAE/g$ TP content and ${\geq}80\;mg\;CE/g$ tannin content. All extracts exhibited ABTS and DPPH radical scavenging ability similar to that of vitamin C. Nitric oxide inhibition activity was lower in the 5 min duration sample than in the 1 min sample. The $4^{\circ}C$ extraction temperature produced an extract with the highest reducing power and hydrogen peroxide values. Extraction temperature also affected sensory evaluation results with the $80^{\circ}C$ extraction temperature producing significantly higher flavor, bitterness, and color score, than those obtained under $4^{\circ}C$ and room temperature extraction conditions.

• Food Science and Preservation
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• v.24 no.1
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• pp.13-20
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• 2017

This study was carried out to investigate the quality characteristics of fried fish paste prepared with different amounts of squeezed Aronia melanocarpa juice. Squeezed Aronia melanocarpa juice (AMJ) was incorporated into fish paste at different levels (containing 2, 7, and 12 g of Aronia melanocarpa juice in 2 AMJ, 7 AMJ, and 12 AMJ, respectively) based on the total weight of water. Sugar contents and total acidity increased with increasing AMJ content. With increasing amounts of AMJ in fried fish paste, L value inside and on the surface decreased, a value increased, and b value inside decreased, whereas b value on the surface increased. pH decreased with increasing levels of AMJ. As the result of textural properties, folding test in all samples showed that AA means good flexibility. The strength, hardness, and chewiness of fried fish paste with AMJ increased while cohesiveness was not significantly different. Total polyphenol contents increased with higher levels of AMJ. DPPH radical scavenging activity was significantly higher than those of the control. In the sensory evaluation, fried fish paste containing 7 AMJ received the highest score than both the control and other samples.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.6-13
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• 2018

Utilizing the heat of cooling water discharge of coal-fired power plant, pipeline investment costs for businesses that supply heat to agricultural facilities near power plants increase in proportion to installation distance. On one hand, the distance from the power plant is a factor that brings difficulties to secure economic efficiency. On the other, if the installation distance is short, there is a problem of securing the heating demands, facility houses, which causes economical efficiency to suffer. In this study, the economic efficiency of 1km length of standard heat pipeline was evaluated. The sensitivity of the heat pipe to the new length variation was analyzed at the level of government subsidy, amount of heating demand and the incremental rate of pipeline with additional government subsidy. As a result of the analysis, it was estimated that NPV 131 million won and IRR 15.73%. The sensitivity analysis showed that NPV was negative when the length of heat pipe facility exceeded 2.6 km. If the government supports 50% of the initial investment, the efficiency is secured within the estimated length of 5.3 km, and if it supports 80%, the length increases within 11.4 km. If the heat demand is reduced to less than 62% at the new length of the standard heat pipe, it is expected economic efficiency is not obtained. If the ratio of government subsidies to initial investment increases, the elasticity of the new bloc will increase, and the fixed investment, which is the cost of capital investment for one unit of heating demand, will decrease. This would result in a reduction in the cost of production per unit, and it would be possible to supply heat at a cheaper price level to the facility farming. Government subsidies will result in the increased economic availability of hot plumbing facilities and additional efficiencies due to increased demand. The greater government subsidies to initial investment, the less farms cost due to the decrease in the price per unit. The results of the study are significant in terms of the economic evaluation of the effectiveness of the government subsidy for the thermal power plant heat utilization project. The implication can be applied to any related pilot to come.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.774-783
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• 2013

This study investigated the quality characteristics of boiled pork with different amounts (0.5, 1, 1.5, or 2%) of green tea, oolong tea and black tea extracts. Characteristics measured included approximate composition, water holding capacity (WHC), hardness, pH, Hunter's color value, total aerobic bacterial counts, volatile basic nitrogen (VBN), 2-thiobarbituric acid reactive substances (TBARS), and sensory qualities. Green tea approximately contained 3.4%, 31.8%, 5.5%, and 57.7% of moisture, crude protein, crude ash, and carbohydrate, respectively. There were no significant differences with the type of tea. However, the crude fat content of green tea, oolong tea, and black tea were 1.6%, 1.0%, and 0.9%, respectively. Green tea had the highest content of crude fat (p<0.05). Boiled pork approximately contained 55.1%, 38.6%, 5.2% and 0.9% moisture, crude protein, crude fat and crude ash, respectively. The WHC of boiled pork, with tea extract added, significantly increased and there were no significant differences according to the type of tea. The hardness of boiled pork significantly increased as the amount of tea extract added increased (p<0.05). The pH of the boiled pork was not significantly different after storage for one day, but significantly decreased in control groups and boiled pork with 0.5% of any tea extract added during storage. However, in boiled pork with 1%, 1.5%, or 2% of any tea extract added, pH was not significantly different during storage. The Hunter's L and b values decreased in all boiled pork. The Hunter's a-values also decreased in boiled pork with green and black tea extract added, but increased in boiled pork with oolong tea extract added. In boiled pork with tea extract added, total aerobic bacterial counts significantly decreased as the amount of tea extract added increased during storage (p<0.05). The VBN values significantly increased during storage in all groups. TBARS values were significantly lower in boiled pork with green tea extract added, oolong tea added (at concentrations of 1%, 1.5%, or 2%), and black tea extract added compared to control groups on the first day. The sensory evaluation results showed that the color, flavor, and overall acceptance of boiled pork containing 1% of oolong or black tea extracts had the highest scores but there were no significant differences. However, taste scores were significantly different (p<0.05). These results indicate that boiled pork has improved quality characteristics with 1% of oolong or black tea extracts added.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.721-726
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• 2010

The objective of this study was to evaluate several varieties of aseptic-packaged cooked rice including Juanbyeo. Quality evaluations, such as by amylose, setback, toyo values and amylograms, were significantly higher in the Juanbyeo as compared to other samples. In addition, the Juanbyeo aseptic-packeged cooked rice showed significantly higher palatability characteristics and had a greater water absorption ratio than the other samples. For cold cooked rice, the relationship between palatability and texture was significantly high (p<0.01). Ilpumbyeo showed high scores for taste as a hot cooked rice, but as a cold cooked rice taste scores were lower than other samples. In the case of Juanbyeo cold cooked rice flavor was improved. When the Juanbyeo aseptic-packaged cooked rice was reheated in a microwave oven, it had better palatability than other varieties. Thus, the results of this study suggested that Juanbyeo can be effectively utilized as aseptic-packaged cooked rice.