• Journal of Korean Society of Coastal and Ocean Engineers
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• 제22권2호
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• pp.79-87
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• 2010

This is the first of the two papers dealing with reliability analyses for external and internal stability of a quay wall constructed on a special foundation. A new practical reliability analysis method is proposed in this paper to evaluate the quantitative risk associated with external stability of a quay wall constructed on the deep cement mixed ground. The method can consider uncertainties in various design variables. For the risk estimation to external stability of the improved soil-quay wall, three corresponding limit state functions of sliding, overturning and bearing capacity are fully defined by introducing concept of the secondary random variable. Three representative reliability methods, MVFOSM, FORM and MCS are then applied to evaluate the failure probabilities of the three limit state functions explicitly expressed in terms of the basic and secondary random variables. From the reliability analysis results, the failure probabilities obtained from the three approaches are very close to each other, and the sliding failure mode appears to be the most critical when the earthquake loading is under consideration.

• Journal of Chest Surgery
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• 제39권1호
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• pp.42-47
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• 2006

Background: The new Multidetector Computed Tomography (MDCT) is useful in visualization of complex coronary artery anatomy. We investigated usefulness comparing of invasive coronary angiography with noninvasive MDCT in judgment of functional degree of coronary arteries grafts after coronary artery bypass graft operation. Material and Method: We analyzed the patency of 52 conduits from 15 patients whom consented to take both 32 Channel MDCT and coronary angiography from November 2003 to November 2004. Comparisons were performed for sensitivity, specificity, positive prediction value and negative prediction value between coronary angiography and 3 dimensional reconstruction image using MDCT. Result: The average graft used was 3.4 $\pm$ 0.8 per patient. Average heart rate during MDCT was 86/minute (Range, 60$\∼$110/minute) without administration of $\beta$-blocker. All patients could hold breath as much as necessary. The average graft patency obtained through corollary angiography was 96.2$\%$. In MDCT group, the sensitivity, the specificity, the positive predictive value and the negative predictive value for diagnosis was 100$\%$, 98.0$\%$, 100$\%$ and 66.6$\%$ respectively. Conclusion: The effectiveness of 32 Channel MDCT may be compared to coronary angiography in grasping about patency and bloodstream of graft conduits after coronary artery bypass graft. Also MDCT has the advantage of noninvasiveness and inexpensiveness compared to coronary angiography.

• Korean Journal of Metals and Materials
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• 제50권4호
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• pp.316-323
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• 2012

The aim of this study is to investigate the effect of post heat treatment on bonding properties of roll cladded Ti/MS/Ti materials. First grade Ti sheets and SPCC mild steel sheets were prepared and then Ti/MS/Ti clad materials were fabricated by a cold rolling and post heat treatment process. Microstructure and point analysis of the Ti/MS interfaces were performed using the SEM and EDX Analyser. Diffusion bonding was observed at the interfaces of Ti/MS. The thickness of the diffusion layer increased with post heat treatment temperature and the diffusion layer was verified as having $({\epsilon}+{\zeta})+({\zeta}+{\beta}-Ti)$ intermetallic compounds at $700^{\circ}C$ and an $({\zeta}+{\beta}-Ti)$ intermetallic compound at $800^{\circ}C$, respectively. The micro Knoop hardness of mild steel decreased with post heat treatment temperature; however, those of Ti decreased at a range of $500{\sim}600^{\circ}C$ and showed a uniform value until $800^{\circ}C$ and then increased rapidly up to $900^{\circ}C$. The micro Knoop hardness value of the diffusion layer increased up to $700^{\circ}C$ and then saturated with post heat treatment. A T-type peel test was used to estimate the bonding forces of Ti/Mild steel interfaces. The bonding forces decreased up to $800^{\circ}C$ and then increased slightly with post heat treatment. The optimized temperature ranges for post heat treatment were $500{\sim}600^{\circ}C$ to obtain the proper formability for an additional plastic deformation process.

• Food Engineering Progress
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• 제23권1호
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• pp.55-61
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• 2019

For the vessel export of strawberries, modified atmosphere package (MAP) using polyamide (PA) film and linear low density polyethylene (LLDPE) film was investigated to extend the shelf life of strawberries. Because the temperature and relative humidity changes of the MAP were lower than the changes of the control, the weight loss of the MAP were lower than that of the control. The low oxygen level and high carbon dioxide level were effective to decrease the fungal decay rate and to increase the hardness of strawberries. The Hunter's color differences before and after storage showed no distinct difference between the MAP and the control. The lightness had a tendency to decrease while the redness increased. There were no significant changes of the soluble solids during the storage. The shelf life of strawberries could be extended to 16 days using the MAP considering the weight loss and the fungal decay rate. Thus, this MAP method using PA film and LLDPE film was effective to extend the shelf life of strawberries.

• Korean Journal of Weed Science
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• 제2권1호
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• pp.1-6
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• 1982

An experiment was conducted to obtain the basic information about competitive ability of rice against weeds as affected by eco-geographic race and plant spacing. Generally, more weeds were grown at the plot of Japonica-type cultivar, (Nakdongbyeo) compared to Tongiltype cultivar (Seogwangbyeo). The degree of weed suppression was highest at the 10 ${\times}$ 10cm plant spacing while no difference was observed between 30 ${\times}$ 15cm and 40 ${\times}$ (10 ${\times}$ 10 cm) plant spacings in both cultivar;. In all treatments except the plot of 10 ${\times}$ 10 cm plant spacing of Seogwangbyeo, singnificant amount of weeds was higher for no weeding plot compared to hand weeding plot. Grain yield loss due to weed competition was the highest at the 40 ${\times}$ (10 ${\times}$ 10cm) plant spacing and followed by 30 ${\times}$ 15cm and 10 ${\times}$ 10cm plant spacing, in order, for Seogwangbyeo. However, for Nakdongbyeo, the highest grain yield loss was obtained from the 30 ${\times}$ 15cm plant spacing and grain yield was not affected at the 10 ${\times}$ 10cm plant spacing. Rice grain yield was highly correlated with weed weight for both cultivars (Seogwangbyeo; Y = 5.44 - 0.0128 X, r = -0.929$^{**}$, Nakdongbyeo; Y = 4.96 - 0.0103 X, r = -0.934$^{**}$). To reduce grain yield by 50%, weed weight of 212.5g/sq.m for Seogwangbyeo and 241g/sq.m for Nakdongbyeo was needed, respectively. This result implied that Nakdongbyeo was more competitive against weeds compared to Seogwangbyeo.

• Journal of Animal Science and Technology
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• 제50권5호
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• pp.657-666
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• 2008

This study investigated the effects of dietary probiotics which contained antioxidant astaxanthin on growth performances and meat quality in two pigs farms. A total of 2,400 pigs were gilt and barrow with same number assigned to one of two treatments. The two treatments were control(commercial feed), treatment(probiotics 0.1% feed). Each treatment had 3 replicates. Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. Survival ratio was shown 99.85% in treatment group. Average daily gain was higher in treatment group(0.91kg) than that of control(0.84kg). Back fat thickness was lower in treatment group than that of control, even though the treatment group tended to be higher carcass weight. The treatment group trended higher carcass weight, back fat thickness was lower in treatment group than control. The ratio of carcass grade A was shown higher in treatment than that of control, respectively. Treatment group showed higher value of fat content and water holding capacity. Treatment showed lower value than control in shear force and cooking loss. Hunter value(a and b) of treatment group in meat color was higher than control. Treatment group was lower cholesterol content than control. Control group was shown higher unsaturated fatty acid(stearic acid(C18:0)) value than treatment. Treatment group was shown lower saturated fatty acid(oleic acid(C18:1)) value than that of control. These results suggested that the supplementation of probiotics contained Phaffia rhodozyma could be used effectively for increase productivity of livestock industry.

• Journal of Animal Science and Technology
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• 제50권4호
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• pp.527-534
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• 2008

Effects of dietary concentrate levels based on whole-crop barley silage (BS) on development and meat quality in growing Korean black goats were examined. A total of 36 male goats with similar age and BW were equally allocated to dietary four treatments in a randomized complete block design. Dietary treatments included controls(rice straw ad libitum plus 2.0% concentrate BW－1), and BS ad libitum plus three increasing levels of concentrate BW－1(2.0, 1.5 and 1.0%, respectively), expressed as BS 2.0, BS 1.5 and BS 1.0, respectively. The trial was lasted for 5 months from 14th of May to 12th of October, 2007. At the end of trial, all animals were slaughtered to analyze carcass characteristics and meat quality. Average daily gain was significantly(p<0.05) higher for BS 1.5 and BS 2.0 treatments than for controls. Daily feed intakes for controls(689.3 g) were significantly(p<0.05) higher than those of BS 1.0(585.5 g), but they were significantly(p<0.05) lower than BS 2.0(734.3 g). Carcass and meat percentages were significantly (p<0.05) higher for BS 2.0 and BS 1.5 than for control and BS 1.0 treatments. Shear force and water-holding capacity was greater(p<0.05) for BS 2.0 and BS 1.5 than other treatments. On the basis of feeding whole-crop barley silage to Korean black goats, as dietary concentrate inclusion levels increased, sensory results showed to have a better tendency. In conclusion, it was estimated that the optimal level of dietary concentrates might be 1.5% BW－1, when diets based whole-crop barley silage were fed to growing Korean black goats for their improvements of growth and meat quality.

• Journal of the Economic Geographical Society of Korea
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• 제14권4호
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• pp.467-485
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• 2011

After Korean War, Korea focused on catching up with the world economy by concentrating on some target industries around the Capital Region and southern coastal cities. Thus, the regional disparity between Capital Region and non-Capital Regions increased drastically. At last, when Korea acquired full-fledged autonomy in 1994 in the Civilian government (1993-1998) and experienced the Asian financial crisis in 1997-1998, local governments were awakened to the notion of region-oriented development, especially for regional industrial development. The purposes of this paper are to introduce regional industrial development policies since 1998 and to suggest some recommendations in terms of how to adjust regional development for industrial policies in the future. In the introducing phase (Kim administration, 1998-2003), four provincial governments requested national funding to raise regional industries that are of strategic importance. At the same time, the central government recognized the need to nurture regional industries to overcome structural weaknesses. As a result, the Roh administration (2003-2008) gave a birth to a systematizing phase. As the ultimate regional policy objective, the balanced national development has been set and the Special Acts, Special Accounts, Committee, and National Plan have been established. Regional Industrial Promotion Project has been carried out very actively during this period. It had a good start albeit idealistic to a certain extent. Therefore, the current government has changed policy paradigm from balanced growth to regional competitiveness along with global paradigm shifts. In order to enhance regional competitiveness, regional development policies have been pursued in more efficient way. Leading Industry Nurturing Projects (LINPs) on Economic Region level, existed Regional Industrial Promotion Projects (RIPPs) on Province level, and Region Specific Industry Projects (RSIPs) on Local Area level have been implemented. Now, it is appropriate to review regional development policies including industrial policies since 1998 and to adjust them for the future sustainable regional development. Because LINPs and RIPPs will be terminated in next two years, the 2nd stage projects are on planning to reduce the redundancies in two projects. In addition, business support program would be reformed from subsiding technology development to building ecological business system. Finally some policy implications are provided in this paper, which is useful to establish the new regional industrial policies for both central and local government.

• Resources Recycling
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• 제15권3호
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• pp.38-45
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• 2006

The thermal filter press dewatering(TFPD) technology to improve the dewaterability through increasing the inner vapor pressure, lowering the filtration viscosity and forming the porosity easily within cake as applying the heat at the sludge layer was developed in this study. The hot water with temperature of $95^{\circ}C$ and pressure of $1.2kg_f/cm^2$ was supplied to the heating plate equipped between filter plates with plate size of $470{\times}470mm$ and material of polypropylene. Sludge was dewaterd by supplying pressure of $5kg_f/cm^2$ and then by squeezing pressure of $15kg_f/cm^2$. As a results of estimating the characteristics of thermal dewatering to consider the initial water content and organic content to be influenced by a period of water shortage and rainwater, the dewatered cake water content was about 35 wt% and dewatering velocity was $4DSkg/m^2{\cdot}hr$ under the rainwater period, and the dewatered cake water content was about 50 wt% and dewatering velocity was $1.5DSkg/m^2{\cdot}hr$ in the case of sludge of water shortage season. These results was superior to the mechanical dewatering performance with water content of 70wt% and dewatering velocity of $0.9DSkg/m^2{\cdot}hr$. On the base of the results of TFPD, energy consumpted to deal with DS(Dry Solid) of 1kg was estimated by 300 kJ. It was analyzed that the energy consumption of TFPD was decreased about one third with comparison to the dryer system. Dewatering velocity of this technology was faster than the one of mechanical dewatering equipment and it was easier to product low water content cake. Therefore, this technology was recognized that dewaterability was predominant because of the fast of dewatering velocity and production of low water content cake, and also this known as economical efficiency was excellent because of low energy consumption in comparison with dryer.

• Korean Journal of Poultry Science
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• 제40권4호
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• pp.315-325
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• 2013

In this study, the effects of Doenjang powder (DP : Korean traditional fermented soy bean paste) addition on the quality and shelf-life of chicken sausages during storage were evaluated. The chicken sausages were manufactured with 60% of chicken breast meat, 20% of chicken skin and other ingredients. The sausages were divided into four treatments according to DP addition level such as 0, 2, 5 and 8%. The sausages were vacuum packed and stored at a refrigerator ($5^{\circ}C$) for 4 weeks. pH of sausage was in creased with DP addition after 2 weeks storage (p<0.05). The addition of 2% and 5% DP decreased the lipid oxidation (TBARS) value (p<0.05) and addition of 8% DP seemed to promote the protein deterioration (VBN) over the storage (p<0.05). In the instrumental color, the chicken sausages with 5% and 8% DP showed higher redness and lower lightness value than sausage with 0 and 2% DP (p<0.05) over the storage. The hardness and gumminess of chicken sausages added with 5% DP were significantly lower than those of other treatments during the storage (p<0.05). The addition of DP detained the growth of aerobic and anaerobic bacteria counts after 2 week of storage (p<0.05), but no significant difference was found by DP addition level (p>0.05). In conclusion, 5% DP could be used as ingredient of chicken sausage to enhance sensory quality and retard lipid oxidation.