• Journal of Korean Society of Transportation
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• v.31 no.6
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• pp.3-11
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• 2013

Under the consumption of bad weather situation affects traffic flows, the study scope is focused on highway capacity and speed variations among other highway traffic flow characteristic changes according to snowfall density. Thus, this study carried out through the data collection and statistical analysis by focusing on capacity and speed changes. Traffic volume, speed and density were selected as factors to explain the property change of a traffic flow for analysis, and 7 basic sections such as 3 highways in Gyeonggi-do and 4 highways near the meteorological observatory were selected as survey points for data collection. Snowfall levels were classified into 3 steps(Light, Medium, Heavy Snow) to analyze the capacity change by snowfall levels. As a result of analysis, the change of capacity depending on snowfall levels decreased 13.2% in case of light snow compared to a good weather, 18.6% in case of medium snow and 32.0% in case of heavy snow, so the capacity reduction rate increased as the snowfall level increased. The worsening weather appeared to have a very big possibility to act as a factor to reduce the operational efficiency of a road, so a road design and operation method considering this should be presented in the future.

• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.257-266
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• 2006

Flat-plate building systems are utilized extensively for construction of apartments, hotels and office buildings because of short construction period, low floor-to-floor height and flexibility in plan design. Recently, to increase lateral seismic resistance of flat-plate building systems, wall-columns are used frequently. Therefore, to estimate strength of flat-plate column connection accurately, the effect of column section shape on the behavior of flat-plate column connection should be considered properly, In the present study, a numerical analysis was performed for interior connections of continuous flat-plate to analyze the effect of column section shape. For the purpose, a computer program for nonlinear FE analysis was developed, and the validity was verified. Through the parametric study, the variations of shear stress distribution around the connection were investigated. According to the result of numerical analysis, as the length of the cross section of column in the direction of lateral load increases, the effective area and the maximum shear strength providing the torsional resistance decrease considerably. Therefore, these effects should be considered properly to estimate the strength of flat-plate connection accurately.

• Food Science and Preservation
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• v.12 no.6
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• pp.591-599
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• 2005

This study was conducted to optimize the extraction conditions from cabbage by a response surface methodology. In extraction conditions based on the central composite design with variations, the ratio of solvent to sample ($10\~30$mL/g), ethanol concentration ($0\~100\%$) and extraction temperature ($35\~95^{circ}C$) coefficients of determinations ($R^2$) were 0.8162(p<0.1), 0.8173(p<0.1), 0.9374(p<0.01) and 0.9116(p<0.05) in extraction yield, electron donating ability, tyrosinase inhibition and SOD-like ability, respectively. Estimated extraction conditions for the maximizing yield, electron donating ability and SOD-like ability were $15\~30$ mL/g in ratio of solvent to sample, $40\~80\%$; ethanol concentration, and $50\~90^{\circ}C$ ; extraction temperature. Predicted values at the optimum condition (25 mL/g solvent to sample, $50\%$ ethanol concentration and $70^{\circ}C$ in extraction temperature) were in good agreement with observed values.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1465-1471
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• 2007

Response surface methodology (RSM) was employed to optimize extraction conditions in order to find the maximal functional properties of fluid Cheonggukjang. Based on central composite design, a study plan was established with variations of microwave power, ethanol concentration, and extraction time. Regression analysis was applied to obtain a mathematical model. The maximum inhibitory of tyrosinase activity was found as 26.75% at the conditions of 30.56W microwave power, 2.40 g/mL of ratio of solvent to sample content and 10.00 min extraction time, respectively. The maximum superoxide dismutase (SOD)-like activity was 53.23% under the extraction conditions of 108.42 W, 4.38 g/mL and 7.84 min. Based on superimposition of three dimensional RSM with respect to extraction yield, inhibitory of tyrosinase activity and SOD-like activity obtained under the various extraction conditions, the optimum ranges of extraction conditions were found to be microwave power of $55{\sim}75$ W, ratio of solvent to sample content of $2{\sim}5$ g/mL and extraction time of $3.5{\sim}15$ min, respectively.

• Korean journal of food and cookery science
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• v.22 no.1 s.91
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• pp.88-95
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• 2006

To enhance the acceptance of hondonbyung ddeuksal, the optimal conditions for the addition of the leaf and root of Angelicae powder were evaluated with the central composite design and response surface methodology. With variations in the mixing ratio of the leaf and root of Angelicae powder, the smell and overall quality of hondonbyung differed significantly, but the color, taste and texture did not. The optimal conditions for the leaf and root content of Angelicae powder, predicted on the basis of each corresponding sensory parameters of hondonbyung ddeuksal, were $2.25\sim3.00%\;and\;0.50\sim0.63%$ for color, 1.55% and 0.85% for smell, 1.95% and 0.80% for taste, $1.00\sim1.22%\;and\;0.58\sim0.99%$ for texture and $2.79\sim3.00%\;and\;0.50\sim0.56%$ for overall quality, respectively. As for hondonbyung komul, there were no significant differences in color, smell, taste, texture or overall quality among the traditional group, and 10% and 20% reduced sweetener' groups.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.911-916
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• 2005

In this study, variations of water quality, sediment size and contaminant substances are analyzed at upstream and downstream in sewer systems in order to evaluate the characteristics of wastewater transformation by physico-chemical and biological reactions. The differences of DOC concentration between up and down stream showed the range of $-5.8{\sim}18.6$ from the result of continuous measurement at up and down stream. About 8.4% of DOC concentration was reduced and reduction rate was 2.3 mg/L/km. SS reduction rate was measured by 5.5 mg/L/km, 0.22 mg/L/min from upstream to downstream, which was twice than DOC reduction rate. When pollution load reduction was evaluated considering infiltration/inflow effect, DOC load was eliminated from 1,230 ka/d to 1,167 kg/d by physi-chemical and biological reaction in a sewer and 7.8% of the SS in upstream station was reduced under dry weather condition. The results showed that the characteristics of transformation process of wastewater in sewer should be considered for design and operation of wastewater treatment plant.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.6
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• pp.585-597
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• 2014

In this study, the cutter acting forces were measured by 3-directional load cell at two different skew angles and various S/d ratios during a series of linear cutting tests using a slim conical pick. The analysis for cutting performance were carried out after calculating average values of the measured results. The increase of penetration depth results in the decrease of specific energy. And the variations of the cutter acting forces depending on penetration depth in the case of 6 degree skew angle were smaller than in the case of 0 degree skew angle. From this results, 6 degree skew angle is more effective than 0 degree skew angle in designing optimal specifications of cutting head. In addition, $F_c/F_n$ under the setting of 6 degree skew angle was smaller than under the setting of 0 degree skew angle. However, it should be considered that the increase of cutter acting force in the cutting direction accompanied the increase of driving force in the case of the setting for 6 degree skew angle.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.563-580
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• 2010

In 2009 the Korea Ministry of Environment announced 'A Comprehensive Plan for the Improvement of Sewer Service in Rural Area' aiming at reduction of the sewer service gap between urban and rural areas as well as improvement in the residential environment of the rural area. According to the plan, the sewer system supply rate for the rural area is expected to reach up to 75% until 2015 with the budget of 4.7 trillion won (Korean currency). It is not certain, however, that the increase in the sewer system supply rate will accompany improvement of water quality in receiving water because several veiled problems that can occur in small-scale sewer treatment plants are poorly addressed in the plan. In this study, those issues for the small-scale sewer treatment plants and their solutions were discussed based on a case study in which we investigated 19 treatment facilities at two rural regions in Gyeonggi province. This study also included strategies useful for the plan. From the results of investigation, some problems, e.g., high hourly variations but low in flowrates and low mass loading were commonly identified. Although operation parameters in sewer treatment plants require to be modified depending on the mass loading, most of the plants were operated with the initial design parameters which causes the decrease of removal efficiency. In the intensive diagnosis, we arranged and applied solutions (e.g., flow equalization, air on/off time control, etc) to the two selected plants and found out improvement of effluent water quality, especially organic matters (COD and SS) and T-N with better denitrification performance.

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.21-29
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• 2008

Objectives : To investigate the therapeutic effects of SBVP in the treatment of patients with cancer-related pain. Design : A prospective randomized, double-blind, placebo-controlled study of SBVP. Setting : The study was conducted at the East West Cancer Center of Daejeon University Dunsan Oriental Hospital from March 1, 2007 to June 20, 2007. Patients : 11 patients diagnosed with cancer-related pain of over 3rd degree on the Numeric Rating Scale(NRS)(0, no pain at all, 10, worst pain imaginable) were entered into a double-blind, placebo-controlled trial of SBVP. They were randomized into Groups A and B(SBVP and control group, respectively) using the table of random sampling numbers and never informed of their affiliation by the coordinator. 5 of 6 patients in Group A and 4 of 5 patients in Group B completed the clinical trial. Intervention : SBVP(1ml/day) for group A and Normal Saline Placebo(1ml/day) for group B was injected into the abdomen acupoint, Zhong Wan(CV 12). The treatment was administered daily for five days. Outcome Measures : Degree of cancer-related pain was measured using the Numeric Rating Scale(NRS) before and after each treatment for "Pain right now" and "Average pain in last 24 hours". Statistical Analysis : Analysis regarding variations in NRS was carried out by applying t-tests(independent sample t-test and paired sample t-test) and Wilcoxon signed rank test with level of significance at 5%. Results : Differences in NRS of "Pain right now" for the two groups were statistically significant. The mean improvement point of SBVP was significantly higher than the control group($2.48^{\circ}{\pm}1.52$ vs $0.97^{\circ}{\pm}1.88$, p<0.05). Differences in average pain score before and after treatment in SBVP group were also significant($5.13^{\circ}{\pm}1.77$ vs $2.65^{\circ}{\pm}0.67$, p<0.05) compared with control group. The two groups showed no significant differences for long term effects in "Average pain in last 24 hours." Conclusion : Although further study will be needed on the large scale, SBVP shows potential as an effective treatment for immediate relief of cancer-related pain.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.947-953
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• 2004

As a large scale port development in coastal waters proceeds step by step and populations in the vicinity of port are getting increased, the issue on 'how to dispose the treated municipal water and wastewater in harbor' brings peoples' concern. The submarine outfall system discharges the primary or secondary treated effluent at the coastline or in deep water, or between these two. The effluent, which has a density similar to that of fresh water, rises to the sea surface forming plume or jet, together with entraining the surrounding sea water and becomes very dilute. We intended in this paper to investigate the impact on dilution of effluent and the behavior of flume under the conditions of the seasonal and spatial temperature variations, which have not been noticeable in designing effective marine outfall system. To predict and analyze the behaviour and dilution characteristics of plume not just with the effluent temperature, but also with the seasonal variation of temperature of surround water, CORMIX( Cornell Mixing Zone Expert System)-GI have been applied. The results should be used with caution in evaluation the mixing zone characteristics of discharged water. We hope to help for the effective operation of outfall system, probable outfall design, protection of water quality, and warm water discharges from a power plant, etc.