• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.23-30
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• 2007

The ultimate objective of this study is to develop oxygen-enriched combustion techniques applicable to the system of practical industrial boiler. To this end the combustion characteristics of lab-scale LNG combustor were investigated as a first step using the method of numerical simulation by analyzing the flame characteristics and pollutant emission behaviour as a function of oxygen enrichment level. Several useful conclusions could be drawn based on this study. First of all, the increase of oxygen enrichment level instead of air caused long and thin flame called laminar flame feature. This was in good agreement with experimental results appeared in open literature and explained by the effect of the decrease of turbulent mixing due to the decrease of absolute amount of oxidizer flow rate by the absence of the nitrogen species. Further, as expected, oxygen enrichment increased the flame temperatures to a significant level together with concentrations of $CO_2$ and $H_2O$ species because of the elimination of the heat sink and dilution effects by the presence of $N_2$ inert gas. However, the increased flame temperature with $O_2$ enriched air showed the high possibility of the generation of thermal $NO_x$ if nitrogen species were present. In order to remedy the problem caused by the oxygen-enriched combustion, the appropriate amount of recirculation $CO_2$ gas was desirable to enhance the turbulent mixing and thereby flame stability and further optimum determination of operational conditions were necessary. For example, the adjustment of burner with swirl angle of $30\sim45^{\circ}$ increased the combustion efficiency of LNG fuel and simultaneously dropped the $NO_x$ formation.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.123-134
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• 2002

An experiment was conducted to establish the most suitable ventilation system for the enclosed nursery pig house in Korea, comparing four different ventilation systems ; i) air enters through perforated ceiling and exhausts through chimney (NA), ii) air enters through perforated ceiling and exhausts through side walls (NB), iii) air enters through perforated ducts and exhausts through side walls (NC) and iv) air enters through perforated ducts and exhausts through chimney(ND). The experiment was carried out during winter and summer separately. The experimental pigs were weaned at fourteen days old in winter (December-February) and at twenty one days old in summer (June-August). The main results of the experiment are as follows : A preliminary experiment showed that in the NC system during summer, air can reach all the pig rooms in the house and the air flow rates of the upper, middle (1.2 m height of the room) and low (at the height of pig stature) parts of the room were measured at 7.0-8.08, over 0.5 and over 0.2 m/s, respectively, which flow rates were much higher(p$<$0.05) than those in other system. At the minimum ventilation efficiency during winter, air flow rates of upper, middle and low parts of the room equipped with the NC system were detected at over 1, less than 0.5 and around 0.07 m/s, respectively. It is concluded that the separated ventilation system air-entering through ducts is the most suitable for the ventilation system of the enclosed nursery pig house and the exhausting system through side walls is more efficient for ventilation than the system through roof. Furthermore, to sustain proper temperature and reduce energy waste as well as heat consumption, a future research should be carried out to develop the environmental control system in relation to developing a heat regulator.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.183-190
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• 2003

Data from live animal real time ultrasound (RTU) measures from 127 Hanwoo steers were used to assess nutritional physiology and relationship between RTU measures and real carcass measures represented meat quality. Traits considered were longissimus muscle area, fat thickness, and marbling score imaged and scanned using RTU by month and those of carcass measures at about 24 month of age. On this study, increasing pattern for longissimus muscle area would be closely related to growth pattern (p<0.01) and it of fat thickness would be related to quadratic effect of ages. Marbling score would be related to aging, that is, individual deviates of scores were distinctly characterized after 17 mo. even though they were started at about 11 mo. Correlation estimates between RTU measures and corresponding carcass traits were over 0.6 after 17 month of age for all traits considered and these estimates were high as 0.90 after 22 month of age. From this study, Real-time ultrasound measurement would be valuable after 15-17 mo. and measures at about 22 mo. would be helpful to decide age for slaughtering. To utilize these techniques for beef cattle breeding via progeny testing program, 15 mo. RTU measures would be efficiency rather than 12 mo. of other beef breeds. Further study to find genetic variation of RTU measures was needed to utilize these technologies for beef breeding.

• Journal of Nutrition and Health
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• v.46 no.1
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• pp.5-14
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• 2013

The anti-obesity effects of fermented black bean were tested with mice fed a high fat diet for seven weeks. Body weight gain and feed efficiency ratio (FER) in the high fat diet control (HC) group were markedly higher, compared with those of the normal control (NC) group, but were significantly lower in the 2% black bean powder supplemented high fat diet (BB) group and 2% black bean powder fermented by M. pilosus supplemented high fat diet (BBM) group, compared with those of the HC group. Food intake in the HC and BB groups was significantly lower than that of the NC and BBM groups. Water intake in the HC group was significantly lower than that of the NC group, but was higher in the BB and BBM groups, compared with that of the HC group. On the other hand, relative liver and kidney weight in the HC group was lower than that of the NC group, but was higher in the BB and BBM groups, compared with that of the HC group. In addition, whereas epididymal fat weight in the HC group was markedly higher than that of the NC group, it was significantly lower in the BB and BBM groups, compared with that of the HC group. Meanwhile, hepatic GSH in the HC group was significantly lower than that of the NC group, but was slightly higher in the BB and BBM groups, compared with that of the HC group. Although hepatic LPO in the HC group was dramatically higher than that of the NC group, it was significantly lower in the BB and BBM groups, compared with that of the HC group. In addition, serum TG, total cholesterol, and LDL-cholesterol in the HC group was significantly higher than that of the NC group, but was significantly lower in the BB and BBM groups, compared with that of the HC group. On the contrary, HDL-cholesterol in the HC group was significantly lower than that of the NC group, but was higher in the BB and BBM groups, compared with that of the HC group. In addition, activity of XOR D type in the HC group was lower than that of the NC group, but was slightly higher in the BB and BBM groups, compared with that of the NC group. Activities of ROS scavenging enzymes, such as SOD, GPX, and GST in the HC group were significantly lower than those of the NC group, but were significantly higher in the BB and BBM groups, compared with those of the HC group. In addition, serum ALT activity in the HC and BB groups was higher than that of the NC group, but was significantly lower in the BB and BBM groups, compared with that of the HC group. In histopathological findings, hepatic fat accumulation in the HC group was higher than that of the NC group, but was lower in the BBM group, compared with that of the HC and BB groups. In particular, antiobese, hypolipidemic, and antifatty liver effect of black bean powder fermented by M. pilosus was specifically higher than that of non-fermented steamed black bean. In conclusion, the constituents of black bean fermented by Monascus pilosus have been proven to not only inhibit obesity and hyperlipidemia but also decrease hepatic fat accumulation in high fat diet-induced obese mice.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.140-148
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• 2015

Purpose: The purpose of this study was to evaluate the role of coffee in diabetic rats in order to prevent hyperglycemia and hyperlipidemia, and to improve antioxidant enzyme activity in streptozotocin induced diabetic rats. Methods: Thirty two male Sprague-Dawley rats (body weight $200{\pm}5g$) were divided into two groups; diabetic and nondiabetic groups. The groups were each randomly divided into two subgroups; fed control and coffee (5 g coffee powder/kg diet) diets. Diabetes was induced by intramuscular injection of 50 mg streptozotocin/kg body weight. Rats with blood glucose concentrations ${\geq}300mg/dL$ were considered diabetic for these experiments. All rats were fed an experimental diet and deionized water ad libitum for 4 weeks. Results: The results of this study indicate that body weight gain was significantly lower in diabetic groups than in nondiabetic groups regardless of diet. Mean food intake was significantly higher in diabetic groups than in nondiabetic groups, and significantly higher in the coffee group than in the control group in diabetic rats. Food efficiency ratio (FER) was significantly lower in diabetic groups than in nondiabetic groups regardless of diet. The fasting blood glucose of coffee supplemented groups was significantly lower compared with the control group in diabetic and nondiabetic rats. The levels of serum LDL-cholesterol and atherogenic index were significantly lower in the coffee group than in the control group in diabetic and nondiabetic rats, and serum HDL-cholesterol was significantly higher in the coffee group than in control groups. The contents of hepatic triglyceride were significantly lower in the coffee group than in the control group in diabetic and nondiabetic rats. The lipid peroxidation of malondialdehyde (MDA) contents was significantly lower in the coffee group than in the control group in diabetic and nondiabetic rats. Activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase in liver was not significantly different by experimental diets among all groups. Conclusion: In conclusion, effects of 0.5% coffee powder supplemented diet were beneficial on blood glucose and lipids in diabetic rats.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.39-58
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• 2019

This study performed the dam watershed storm runoff modeling using GPM(Global Precipitation Measurement) satellite rain and KIMSTORM2(KIneMatic wave STOrm Runoff Model 2) distributed model. For YongdamDam watershed(930㎢), three heavy rain events of 25th August 2014, 11th September 2017, and 26th June 2018 were selected and tested for 4 cases of spatial rainfalls such as (a) Kriging interpolated data using ground observed data at 7 stations, (b) original GPM data, (c) GPM corrected by CM(Conditional Merging), and GPM corrected by GDA(Geographical Differential Analysis). For the 4 kinds of data(Kriging, GPM, CM-GPM, and GDA-GPM), the KIMSTORM2 was calibrated respectively using the observed flood discharges at 3 water level gauge stations(Cheoncheon, Donghyang, and Yongdam) with parameters of initial soil moisture contents, stream Manning's roughness coefficient, and effective hydraulic conductivity. The total average Nash-Sutcliffe efficiency(NSE) for the 3 events and 3 stations was 0.94, 0.90, 0.94, and 0.94, determination coefficient(R²) was 0.96, 0.92, 0.97 and 0.96, the volume conservation index(VCI) was 1.03, 1.01, 1.03 and 1.02 for Kriging, GPM, CM-GPM, and GDA-GPM applications respectively. The CM-GPM and GDA-GPM showed better results than the original GPM application for peak runoff and runoff volume simulations, and they improved NSE, R², and VCI results.

• Journal of the Korea Concrete Institute
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• v.18 no.5 s.95
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• pp.687-693
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• 2006

The Stone Powder Sludge(below SPS) is the by-product from the process that translates stone power of 8mm under as crushed fine aggregate. It is the sludge as like cake that has average particle size of $7{\mu}m$, absorbing water content of 20 to 60%, and $SiO_2$ content of 60% over. Because of high water content of SPS, it is not only difficult to handle, transport, and recycle, but also makes worse the economical efficiency due to high energy consuming to drying. This study is aim to recycle SPS as it is without drying. Target product is the lightweight foamed concrete that is made from the slurry mixed with pulverized mineral compounds and foams through hydro-thermal reaction of CaO and $SiO_2$. Although in the commercial lightweight foamed concrete CaO source is the cement and $SiO_2$ source is high purity silica powder with $SiO_2$ of 90%, we tried to use the SPS as $SiO_2$ source. From the experiments with factors such as foam addition rate and replacement proportion of SPS, we find that the lightweight foamed concrete with SPS shows the same trends as the density and strength of lightweight foamed concrete increases according to decrease of foam addition rate. But in the same condition, the lightweight foamed concrete with SPS is superior strength and density to that with high purity silica. This trends is distinguished according to increase of replacement proportion of SPS, also the analysis of XRF shows that the hydro thermal reaction translates SPS to tobermorite. Although SPS has low $SiO_2$ contents, the lightweight foamed concrete with SPS has superior strength and density, because it reacts well with CaO due to extremely fine particles. We conclude that it is possible to replace the high purity silica as SPS in the lightweight foamed concrete experimentally.

• Asia pacific journal of information systems
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• v.19 no.1
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• pp.113-145
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• 2009

Recently, due to the globalization of the IT(Information Technology) market, devices and systems designed in one country are used in other countries as well. This phenomenon is becoming the key factor for increased interest on cross-cultural, or cross-national, research within the IT area. However, as the IT market is becoming bigger and more globalized, a great number of IT practitioners are having difficulty in designing and developing devices or systems which can provide optimal experience. This is because not only tangible factors such as language and a country's economic or industrial power affect the user experience of a certain device or system but also invisible and intangible factors as well. Among such invisible and intangible factors, the cultural characteristics of users from different countries may affect the user experience of certain devices or systems because cultural characteristics affect how they understand and interpret the devices or systems. In other words, when users evaluate the quality of overall user experience, the cultural characteristics of each user act as a perceptual lens that leads the user to focus on a certain elements of experience. Therefore, there is a need within the IT field to consider cultural characteristics when designing or developing certain devices or systems and plan a strategy for localization. In such an environment, existing IS studies identify the culture with the country, emphasize the importance of culture in a national level perspective, and hypothesize that users within the same country have same cultural characteristics. Under such assumptions, these studies focus on the moderating effects of cultural characteristics on a national level within a certain theoretical framework. This has already been suggested by cross-cultural studies conducted by scholars such as Hofstede(1980) in providing numerical research results and measurement items for cultural characteristics and using such results or items as they increase the efficiency of studies. However, such national level culture has its limitations in forecasting and explaining individual-level behaviors such as voluntary device or system usage. This is because individual cultural characteristics are the outcome of not only the national culture but also the culture of a race, company, local area, family, and other groups that are formulated through interaction within the group. Therefore, national or nationally dominant cultural characteristics may have its limitations in forecasting and explaining the cultural characteristics of an individual. Moreover, past studies in psychology suggest a possibility that there exist different cultural characteristics within a single individual depending on the subject being measured or its context. For example, in relation to individual vs. collective characteristics, which is one of the major cultural characteristics, an individual may show collectivistic characteristics when he or she is with family or friends but show individualistic characteristics in his or her workplace. Therefore, this study acknowledged such limitations of past studies and conducted a research within the framework of 'theoretically integrated model of user satisfaction and emotional attachment', which was developed through a former study, on how the effects of different experience elements on emotional attachment or user satisfaction are differentiated depending on the individual cultural characteristics related to a system or device usage. In order to do this, this study hypothesized the moderating effects of four cultural dimensions (uncertainty avoidance, individualism vs, collectivism, masculinity vs. femininity, and power distance) as suggested by Hofstede(1980) within the theoretically integrated model of emotional attachment and user satisfaction. Statistical tests were then implemented on these moderating effects through conducting surveys with users of four digital devices (mobile phone, MP3 player, LCD TV, and refrigerator) in three countries (US, Germany, and Russia). In order to explain and forecast the behavior of personal device or system users, individual cultural characteristics must be measured, and depending on the target device or system, measurements must be measured independently. Through this suggestion, this study hopes to provide new and useful perspectives for future IS research.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.811-818
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• 2010

This study was carried out to investigate the effect of different herb resource powders on meat quality and sensory properties in Korean native black goat for 500 d. The experimental treatment was arranged with 24 heads (3 treatment/8 heads) by control group, T1 and T2 group respectively (Control, not added herb powders; T1, 1% added herb powders; T2, 2% added herb powders). Total weight gain for the Korean native black goat was the highest in T2 group feeding for 500 days, and daily gain tended to be similar to the total weight gain. The total feed intake were the highest as 519.20 kg in T2 group, although feed conversion showed 18.35 in the T2 group, which means it had the best feed efficiency compared to the other treatment groups. The carcass rate was higher in the T1 group (51.10%) than in the other groups (p<0.05). The cooking loss and drip loss of Korean native black goat was the highest as 34.72% and 3.83% in the control group (p<0.05). However, total cholesterol amounts in the treatment group were not significantly different from, although tended to be higher than, the control group (p>0.05). Also, the overall sensory evaluation of the treatment group revealed low scores, meaning more meat flavor than those of the control in tenderness, flavor, texture, and black goat off-flavor and overall evaluation (p<0.05). Total synthesis evaluation was higher for the treatment group (3.71, 3.90 point) than that of the control group (4.82 point) (p<0.05). The MUFA/SFA ratio of the treatment group was not significantly different from, although tended to be higher than, the control group

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.