• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.58 no.4
• /
• pp.424-431
• /
• 2013

Consumption of waxy corn is steadily increasing due to consumer preference for natural food. However, availability of waxy corn is limited because most of them are used for steamed waxy corn. It is therefore important to create new demands of waxy corn using food processing technology. There is little prior research about characteristics of milled kernel in waxy corn. This study examined the physicochemical and cooking properties of milled kernel using nine waxy corn hybrids. Colored hybrids (Heukjinju, Miheukchal, and Eolrukchal1) showed high milling yield and low change of grain length after milling process compared to other hybrids. The total starch content ranged from 62.1 to 68.4% and the gelatinization temperature of starch was lowest in Yeonnong1 ($69.9^{\circ}C$). The breakdown viscosity of Yeonnong1, Miheukchal and Heukjinju was higher than those of tested hybrids, whereas setback viscosity of those hybrids was lower. In cooking properties of milled waxy corn, water absorption and volume expansion rate were high in Yeonnong2 (84.9, 219.3%), Miheukchal (85.9, 211.4%), and Heukjinju (80.9, 203.7%). In the sensory test, the overall preference was significantly higher in Heukjinju and Miheukchal. Thus, Heukjinju, Yeonnong2, and Miheukchal showed good scores in milling yield, cooking properties, and the preference of sensory test. These results will provide fundamental information to extend milled waxy corns usage.

• Journal of Chest Surgery
• /
• v.39 no.7 s.264
• /
• pp.505-510
• /
• 2006

Background: Small animal cardiopulmonary bypass (CPB) model would be a valuable tool for investigating path-ophysiological and therapeutic strategies on bypass. The main advantages of a small animal model include the reduced cost and time, and the fact that it does not require a full scale operating environment. However the rat CPB models have a number of technical limitations. Effective maintenance and control of core temperature by a heat exchanger is among them. The purpose of this study is to confirm the effect of rectal temperature maintenance using a heat exchanger of cardioplegia system in cardiopulmonary bypass model for rats. Material and Method: The miniature circuit consisted of a reservoir, heat exchanger, membrane oxygenator, roller pump, and static priming volume was 40 cc, Ten male Sprague-Dawley rats (mean weight 530 gram) were divided into two groups, and heat exchanger (HE) group was subjected to CPB with HE from a cardioplegia system, and control group was subjected to CPB with warm water circulating around the reservoir. Partial CPB was conducted at a flow rate of 40 mg/kg/min for 20 min after venous cannulation (via the internal juglar vein) and arterial cannulation (via the femoral artery). Rectal temperature were measured after anesthetic induction, a ter cannulation, 5, 10, 15, 20 min after CPB. Arterial blood gas with hematocrit was also analysed, 5 and 15 min after CPB. Result: Rectal temperature change differed between the two groups (p<0.01). The temperatures of HE group were well maintained during CPB, whereas control group was under progressive hypothermia, Rectal temperature 20 min after CPB was $36.16{\pm}0.32^{\circ}C$ in the HE group and $34.22{\pm}0.36^{\circ}C$ in the control group. Conclusion: We confirmed the effect of rectal temperature maintenance using a heat exchanger of cardioplegia system in cardiopulmonary bypass model for rats. This model would be a valuable tool for further use in hypothermic CPB experiment in rats.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.21 no.1
• /
• pp.31-48
• /
• 2019

The artificial ground freezing (AGF) method is a groundwater cutoff and/or ground reinforcement method suitable for constructing underground structures in soft ground and urban areas. The AGF method conducts a freezing process by employing a refrigerant circulating through a set of embedded freezing pipes to form frozen walls serving as excavation supports and/or cutoff walls. However, thermal expansion of the pore water during freezing may cause excessive deformation of the ground. On the other hand, as the frozen soil is thawed after completion of the construction, mechanical characteristics of the thawed soil are changed due to the plastic deformation of the ground and the rearrangement of soil fabric. This paper performed a field experiment to evaluate the freezing rate of marine clay in the application of the AGF method. The field experiment was carried out by circulating liquid nitrogen, which is a cryogenic refrigerant, through one freezing pipe installed at a depth of 3.2 m in the ground. Also, a piezo-cone penetration test (CPTu) and a lateral load test (LLT) were performed on the marine clay before and after application of the AGF method to evaluate a change in strength and stiffness of it, which was induced by freezing-thawing. The experimental results indicate that about 11.9 tons of liquid nitrogen were consumed for 3.5 days to form a cylindrical frozen body with a volume of about $2.12m^3$. In addition, the strength and stiffness of the ground were reduced by 48.5% and 22.7%, respectively, after a freezing-thawing cycle.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.25 no.2
• /
• pp.63-75
• /
• 2013

The Inner Port Phase 2 area of the Pyeongtaek-Dangjin Port is enclosed by a total of three permeable sea-walls, and the disposal site to the east of the Inner Port Phase 2 is also enclosed by two permeable sea-walls. The maximum tidal range measured in the Inner Port Phase 2 and in the disposal site in May 2010 is 4.70 and 2.32 m, respectively. It reaches up to 54 and 27%, respectively of 8.74 m measured simultaneously in the exterior. Regression formulas between the difference of hydraulic head and the rate of interior water volume change, are induced. A three-dimensional numerical hydrodynamic model for the Asan Bay is constructed incorporating a module to compute water discharge through the permeable sea-walls at each computation time step by employing the formulas. Hydrodynamics for the period from 13th to 27th May, 2010 is simulated by driving forces of real-time reconstructed tide with major five constituents($M_2$, $S_2$, $K_1$, $O_1$ and $N_2$) and freshwater discharges from Asan, Sapkyo, Namyang and Seokmoon Sea dikes. The skill scores of modeled mean high waters, mean sea levels and mean low waters are excellent to be 96 to 100% in the interior of permeable sea-walls. Compared with the results of simulation to obstruct the flow through the permeable sea-walls, the maximum current speed increases by 0.05 to 0.10 m/s along the main channel and by 0.1 to 0.2 m/s locally in the exterior of the Outer Sea-wall of Inner Port. The maximum bottom shear stress is also intensified by 0.1 to 0.4 $N/m^2$ in the main channel and by more than 0.4 $N/m^2$ locally around the arched Outer Sea-wall. The module developed to compute the flow through impermeable seawalls can be practically applied to simulate and predict the advection and dispersion of materials, the erosion or deposion of sediments, and the local scouring around coastal structures where large-scale permeable sea-walls are maintained.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.5B
• /
• pp.603-614
• /
• 2008

End-uses of household water have been changed by a life style, housing type, weather, water rate and water supply facilities etc. and those variables can be considered as an internal and exogenous factors to estimate long-term demand forecasts. Analysis of influential factors on water consumption in households would give an explanation to cause on the change of trend and would help predicting the water demand of end-use in household. The purpose of this study is to analyze the demand trends and patterns of household water uses by metering and questionnaire such as occupation, revenue, numbers of family member, housing types, age, floor area and installation of water saving device, etc. The peak water uses were shown at Saturday among weekdays and July in a year based on the analysis results of water use pattern. A steep increase of total water volume can be found in the analysis of water demand trend according to temperature from $-14^{\circ}C$ to $0^{\circ}C$, while there are no significant variations in the phase of more than $0^{\circ}C$, with an almost stable demand. Washbowl water shows the highest and toilet water shows the lowest relation with temperature in correlation analysis results. In the results of ANOVA to find the significant difference in each unit water use by exogenous factors such as housing type, occupation, number of generation, residential area and income et al., difference was shown in bathtub water by housing type and shown in kitchen, toilet and miscellaneous water by numbers of resident. Especially, definite differences in components except washbowl and bathtub water, could be found by numbers of resident. Based on the result, average residents in a house should be carefully considered and the results can be applied as reference information, in decision making process for predicting water demand and establishing water conservation policy. It is expected that these can be used as design factors in planning stage for water and wastewater facilities.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.51 no.4
• /
• pp.101-118
• /
• 2023

During the COVID-19 pandemic, the utilization rate of neighborhood parks and green spaces increased significantly, and the outbreak served as an opportunity to highlight the values and functions of neighborhood parks and green spaces for urban residents. This study aims to empirically analyze how citizens' movement and the use of neighborhood parks and green spaces changed before and after COVID-19 and examine the social and spatial characteristics that affected these changes. As a research method, first, people's mobility around neighborhood parks and green spaces before and after the COVID-19 pandemic were compared using signal data from telecommunication carriers. Through the analysis of changes in residence time and movement volume, the movement characteristics of citizens after COVID-19 and changes in walking-based park visits were examined. Second, the factors affecting the mobility change in neighborhood parks and green spaces were analyzed. The social and spatial characteristics that affect citizens' visits to neighborhood parks and green spaces before and after COVID-19 were examined through correlation and multiple regression analysis. Subsequently, through cluster analysis, the types of living areas for the post-COVID era were classified from the perspective of the supply and management of neighborhood parks and green spaces services, and directions for improving neighborhood parks and green spaces by type were presented. Major research findings are as follows: First, since the outbreak of COVID-19, activities within 500m of the residence have increased. The amount of stay and walking movement increased in both 2020 and 2021, which means that the need to review the quantitative standards and attractions of neighborhood parks and green spaces has increased considering the changed scope of the walking and living area. Second, the overall number of visits to neighborhood parks and green spaces by walking has increased since the outbreak of COVID-19. The number of visits to neighborhood parks and green spaces centered on the house and the workplace increased significantly. The park green policy in the post-COVID era should be promoted by discovering underprivileged areas, focusing on areas where residential, commercial, and business facilities are concentrated, and improving neighborhood parks and green services in quantitative and qualitative terms. Third, it was found that the higher the level of park green service, the higher the amount of walking movement. It is necessary to use indicators that contribute to improving citizens' actual park green services, such as walking accessibility, rather than looking at the criteria for securing green areas. Fourth, as a result of cluster analysis, five types of neighborhood parks and green spaces were derived in response to the post-COVID era. This suggests that it is necessary to consider the socioeconomic status and characteristics of living areas and the level of park green services required in future park green policies. This study has academic and policy significance in that it has laid the basis for establishing neighborhood parks and green spaces policy in response to the post-COVID era by using various analysis methodologies such as carrier signal data analysis, GIS analysis, and statistical analysis.

• Clinical and Experimental Pediatrics
• /
• v.45 no.2
• /
• pp.214-222
• /
• 2002

Purpose : The aim of this study was to evaluate myocardial injury in children treated with adriamycin by echocardiography, which is non-invasive and safe measurement for children. Methods : Left ventricular dimensions, wall stress, and contractile function were determined by echocardiographic methods in 17 patient recepients with adriamycin chemotherapy at rest(group 1) and during stress(group 2). Twenty age-matched normal subjects were established as control group. Results : End-diastolic dimension was decreased in both groups(group 1; $92{\pm}7%$ of normal, group 2; $87{\pm}8%$ of normal, P<0.05). Left ventricular end diastolic volume and wall mass were also decreased in both groups(group 1; $96{\pm}12mL/m^2$ and $145{\pm}18g/m^2$, group 2; $87{\pm}8mL/m^2$ and $137{\pm}16g/m^2$, respectively, P<0.05 and P<0.05) and group 2 showed lower values than group 1. Meridional end systolic stress(ESSm) was increased in both groups but there was no significant difference between the two groups(group 1; $52.6{\pm}6.2g/cm^2$, group 2; $63.5{\pm}8.5g/cm^2$, P<0.05, normal value $45.7{\pm}3.5g/cm^2$). The load-independent relation of rate-corrected circumferential fiber shortening velocity(Vcfc) to ESSm has a significant abnormal change in 7 out of 17(41%) in group 1 and 12 out of 17(71%) in group 2. Conclusion : The load-dependent systolic index, such as fractional shortening, may fail to show abnormality because of the compensatory changes in preload and afterload which can mask the impaired contractility. Therefore, systolic performance also should be monitored by a load-indepedent contractility index such as slope value of the end-systolic pressure-dimension relation and the position of the left ventricular stress-fiber shortening velocity after exercise.

• Economic and Environmental Geology
• /
• v.34 no.1
• /
• pp.1-12
• /
• 2001

The crystal structure of biotite-1M from Bancroft, Ontario, was determined by Rietveld refinement method using high-resolution neutron powder diffraction data at -26.3$^{\circ}C$, 2$0^{\circ}C$, 30$0^{\circ}C$, $600^{\circ}C$, 90$0^{\circ}C$. The crystal structure has been refined to a R sub(B) of 5.06%-11.9% and S (Goodness of fitness) of 2.97-3.94. The expansion rate of a, b, c unit cell dimensions with elevated temperature linearly increase to $600^{\circ}C$. The expansivity of the c dimension is $1.61{\times}10^{40}C^{-1}$, while $2.73{\times}10^{50}C^{-1}$ and $5.71{\times}10^{-50}C^{-1}$ for the a and b dimensions, respectively. Thus, the volume increase of the unit cell is dominated by expansion of the c axis as increasing temperature. In contrast to the trend, the expansivity of the dimensions is decreased at 90$0^{\circ}C$. It may be attributed to a change in cation size caused by dehydroxylation-oxidation of $Fe^{2+}$ to $Fe^{3+}$ in vacuum condition at such high temperature. The position of H-proton was determined by the refinement of diffraction pattern at low temperature (-2.63$^{\circ}C$). The position is 0.9103${\AA}$ from the O sub(4) location and located at atomic coordinates (x/a=0.138, y/b=0.5, z/c=0.305) with the OH vector almost normal to plane (001). According to the increase of the temperature, $\alpha$* (tetrahedral rotation angle), $t_{oct}$ (octahedral sheet thickness), mean distance increase except 90$0^{\circ}C$ data. But the trend is less clearly relative to unit cell dimension expansion because the expansion is dominant to the interlayer. Also, ${\Psi}$ (octahedral flattening angle) shows no trends as increasing temperature and it may be because the octahedron (M1, M2) is substituted by Mg and Fe.

• Korean Journal of Environmental Agriculture
• /
• v.37 no.4
• /
• pp.268-276
• /
• 2018

BACKGROUND: In the month of January 2018, fine dust alerts and warnings were issued 36 times for $PM_{10}$ and 81 times for PM2.5. Air quality is becoming a serious issue nation-wide. Although interest in air-purifying plants is growing due to the controversy over the risk of chemical substances of regular air-purifying solutions, industrial spread of the plants has been limited due to their efficiency in air-conditioning perspective. METHODS AND RESULTS: This study aims to propose a vegetation-based bio-filter system that can assure total indoor air volume for the efficient application of air-purifying plants. In order to evaluate the quantitative performance of the system, time-series analysis was conducted on air-conditioning performance, indoor air quality, and comfort index improvement effects in a lecture room-style laboratory with 16 persons present in the room. The system provided 4.24 ACH ventilation rate and reduced indoor temperature by $1.6^{\circ}C$ and black bulb temperature by $1.0^{\circ}C$. Relative humidity increased by 24.4% and deteriorated comfort index. However, this seemed to be offset by turbulent flow created from the operation of air blowers. While $PM_{10}$ was reduced by 39.5% to $22.11{\mu}g/m^3$, $CO_2$ increased up to 1,329ppm. It is interpreted that released $CO_2$ could not be processed because light compensation point was not reached. As for the indoor comfort index, PMV was reduced by 83.6 % and PPD was reduced by 47.0% on average, indicating that indoor space in a comfort range could be created by operating vegetation-based bio-filters. CONCLUSION: The study confirmed that the vegetation-based bio-filter system is effective in lowering indoor temperature and $PM_{10}$ and has positive effects on creating comfortable indoor space in terms of PMV and PPD.

• Journal of the Korean Magnetics Society
• /
• v.26 no.5
• /
• pp.173-178
• /
• 2016

This study is to evaluate the effect of a Contrast Media (CM) on dose calculations and clinical significance in Radiation (Electromagnetic wave) Therapy (RT) plans for head & neck (H&N) and prostate cancer. Pinnacle 8.0 system was used to measure the change of Electron Density (ED) of the tissue for CM. To determine the effect of dose calculation due to CM, we did the RT planning for 30 patients. To compare the ED and dose calculations of RT plans, 3D CRT and IMRT plans were do with pinnacle and Tomotherapy planning system. Mean difference of ED between enhanced and unenhanced CT was less than 4%: H&N Target Volume (TV) 2.1%, parotid 1.9%, SMG 3.6%, tongue 0.9%, spinal cord 0.3%, esophagus 2.6%, mandible 0.1% and prostate TV 0.7%, lymph node 1.1%, bladder 1.2%, rectum 1.5%, small bowel 1.2%, colon 0.6%, penile bulb 0.8%, femoral head -0.2%. The dose difference between RT plan using CM and without CM showed an increase of dose in TV. The rate of increase was less than 2.5% (3D CRT: H&N 0.69~2.51%, prostate 0.04~1.14%, IMRT: H&N 0.58~1.31%, prostate 0.36~1.04%). RT plans using a CM has the insignificant effect on the organs and TV, so this error is allowable clinically. However, the much more accurate plan is possible as to image fusion (CM and without CM images) to ROI contour and when dose calculation, use the without CM image. Using the fusion of 'ROI import' perform calculations on without CM, it will be able to reduce the error (1~3%) caused by the CM.