• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1171-1177
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• 1999

The changes on microstucture of recombinated gels with different ratio of amylose(A) and amylopectin(AP) which were isolated from nonwaxy rice starch were investigated by scanning electron microscope(SEM) and X-ray diffractometer. As the concentration of amylose was above 3%(1.08% of soluble amylose) in the amylose suspension, gel matrix became like a three-dimensional network. The microstructure of amylose gels showed a network including macroporous structure, but the higher the ratio of amylopectin content were, the firmer network were formed. In case of A/AP mixed gels(15%) with different amylose/amylopectin percent ratios ; 0/5, 5/10, 10/5, 15/0%, as the storage time of gels and the percent ratio of amylose content were increased, network was formed harder with thick films. While X-ray diffractograms of waxy rice starch which contained 100% amylopectin showed A type, those of purified amylose and amylopectin showed V type and amorphous patterns, respectively. Amylose(3%) gels added $2{\sim}3%$ amylopectin and A/AP mixed gels(15%) showed peak at $2{\theta}\;=\;17.0^{\circ}$which were shown B type crystallinity similar af retrograded starches. Also as the percent ratio of amylose content in mixed gels was increased, peak intensity wat increased.

• Journal of the Korean GEO-environmental Society
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• v.10 no.3
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• pp.5-12
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• 2009

This study presents static and dynamic strength of coal ashes collected from disposal site of power plant. Main compositions of coal ashes were bottom ashes. In order to evaluate static and dynamic characteristics of coal ash, NGI direct-simple shear tests, cyclic simple shear tests and direct shear tests were conducted. The strengths of coal ashes from those tests were compared to those of sands. Bottom ashes among coal ashes used for this study were classified as sand from the grain size distribution and show higher strength properties than the sands. For utilization of coal ashes in civil engineering project, mixing coal ashes with sandy soil using batch plant is inconvenient and the cost is higher than the spreading sand layer and coal layer alternately. In order to simulate both mixing type and layered type construction, sands and coal ashes were mixed with volume ratio 50:50 and prepared sand and coal ash layers alternately with the same volume ratio. From the tests mixed coal ashes-specimen shows slightly higher static and cyclic strength than the layered specimen at the same density. The higher strength seems due to the angular grain of bottom ashes. The cyclic stress ratio at liquefaction decreases rapidly as the number of cycle increases at mixed specimen than that of layered specimen.

• Journal of the Korean Geotechnical Society
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• v.22 no.1
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• pp.45-52
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• 2006

A theoretical equation, from which we can get a suitable ratio of bentonite at bentonite-mixed soil, was derived for desigri of the impermeable condition. Bentonite is a soil with great expansion property and it has the permeability lower than $1\times10^{-7}cm/sec$ in spite of its maximum expansion state. Accordingly if the void of soil is filled with the liquid of bentonite, water will flow only through the veid of bentonite liquid. And the permeability of bentonite-mixed soil will always satisfy the condition as impermeable zone. However, because it is very difficult to mix uniformly bentonite with soil, it is thought that the actual mixing ratio fur the impermeable zone will be grater than that by theoretical equation. Permeability tests were performed to check the equation and a modified equation was suggested from the experimental results.

• Journal of Energy Engineering
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• v.11 no.4
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• pp.283-290
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• 2002

Numerical calculations have been carried out for the mixed convection flow in a concentric curved annulus with constant heat flux boundary condition at inner wall. The flow is assumed to be fully developed so as to maintain a constant streamwise pressure and temperature gradient. Computations have been performed for flows of radius ratio 0.2 and 0.5 with the Dean number lying in the range 0$K^{1/2}$ for the wide range of the Dean number considered here.

• Journal of Biosystems Engineering
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• v.24 no.6
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• pp.487-492
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• 1999

One of effective utilization method of rice husk is to utilize it as culture material by carbonizing the rice husk. As a second part of a series to investigate the effective and continuous production of carbonized rice husk by a cyclone combustor, a non-slagging vertical cyclone combustor without vortex collector pocket was introduced. Isothermal and mixed firing with LPG and rice husk were undertaken in order to characterize the system. Inert rice husk was used during the isothermal test to find mass of rice husk collected. It was impossible to ignite rice husk itself over the experimental conditions considered in this experiment. Cyclone combustor was operated at temperatures of 1,273~1,473K. Detailed combustion data were obtained from a pilot unit with the air flow rate of 70m$^3$/h and rice husk feed of 2kg. The equivalence ratio ranged from 0.66 to 3.48. The auxiliary gas flow rate was varied from 3.22 to 12.86$\ell$/min. The weight reduction, pH and particle size distribution of carbonized rice husk were measured to evaluate the quality of carbonized rice husk. An analysis of exhaust gas emission was conducted to characterize the combustor. The required carbonized rice husk could be obtained at equivalence ratio of 1.68~2.17, combustor temperature of 1,273~1,373K and auxiliary gas flow rate of 3.22~6.43$\ell$/min. A method to reduce CO emissions should be employed.

• Journal of Nutrition and Health
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• v.26 no.5
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• pp.513-523
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• 1993

In this experiment, we investigated the hypolipidemic and antithrombotic effects of rats fed diets with different common oils in Korea for different feeding periods(4 weeks or 12 weeks), using Korean sesame oil, perilla oil, rice bran oil and mixed oil. W-3/w-6 ratio of each group was 0.001, 1.44, 0.03 and 0.112, respectively. P/S ratio of each group was 9.64, 10.49, 5.58 and 1.68, respectively. The result were as follows: 1) According to the age, body fat accumulation was increased. 2) Perilla oil(w-3 rich) decreased total lipid, triglyceride and total cholesterol, and increased HDL/total cholesterol ratio. 3) With regard to the compositono of platelet fatty acids, Perilla oil increased w-3/w-6 ratio of the platelet. Perilla oil lengthened bleeding time and decreased MDA(MalonDAdehyde) formation which determined in place of Thromboxane A2(TXA2) in platelet. This result can suggest that linoleic acid of perrilla oil seem to supress the conversion of linoleic acid to arachidonic acid(AA 20:4, w-6) and eicosapentaenoic acid(EPA, 20:5, w-3) trannnsformed from linolenic acid to suppress the conversion of arachidonic acid to TXA2. Since TXA2 is platelet-aggregating and vasoconstricting agent, the reduction of TXA2 tgeneration by platelet with increased linolenic acid intakes shows prologed bleeding time. In conclusion, w-3 rich perilla oil has strong hypolipidemic and antithrombotic effects by changing fatty acid profiles of the platelet.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.12
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• pp.1848-1856
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• 2008

In order to enhance the functionality of a cotton fabric actually used as the clothing material for patients, the fabrics are treated with chitosan/nanosilver mixed solution. The nanosilver has excellent biocompatibility, not causing an environmental pollution as a natural polymer, provides expectation of an additional performance, does not harm human beings, and shows a strong antibacterial activity even in a small amount, and supplements chitosan, which is disadvantaged if used alone for fabric treatment. This study evaluates functional improvement of the clothing material for patients and observes through hygienic characteristics which are the most important function. In antibacterial activity of the fabrics treated with chitosan/nanosilver mixed solution against Staphylococcus aureus, higher ratio of chitosan was observed to achieve better antibacterial activity. In antibacterial activity against Klebsiella pneumoniae, higher ratio of nanosilver was observed to achieve better activity. Regarding laundry durability of antibacterial activity after repeated laundering, activity against Staphylococcus aureus was little reduced, but was greatly lowered against Klebsiella pneumoniae. Deodorization activity was excellent as the mixed ratio of chitosan was increased, and air permeability, moisture permeability and moisture regain were reduced as the mixed ratio of nanosilver was increased.

• Journal of the Korean Institute of Gas
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• v.21 no.2
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• pp.1-9
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• 2017

Enhanced coalbed methane recovery (ECBM), as injecting $CO_2$ or $N_2$ into the coalbed methane (CBM) reservoir for increasing methane recovery, takes center stage in these days. ECBM makes a better recovery than the conventional production method, it called dewatering process. However the characteristics of injection gas affect to methane recovery, thus analysis on the mixed ratio of injection gas should be required. In this study, CBM reservoir model was built to estimate the methane recovery of ECBM method by different mixed ratio of injection gas. Additionally, to consider the characteristics of injection gas such as carbon captured storage, nitrogen re-injection, etc. economic analysis was performed. The results showed that ECBM cases produced methane almost twice as much as dewatering case and $CO_2$ 10% and $N_2$ 90% case resulted in the highest methane recovery among the mixed gas cases. On the other hand, the results of economic analysis showed that $CO_2$ 20% and $N_2$ 80% case made the highest total production profit. Therefore, both the recovery of methane and economical efficiency should be considered to apply ECBM process.

• Journal of Navigation and Port Research
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• v.38 no.5
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• pp.527-539
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• 2014

This study establishes the research model and sets up the hypothesis in order to analyze the effect of the type of mixed manning and the ratio of foreign crew on the group cohesiveness, job satisfaction and organizational commitment in ship organizations and the moderating effect of the acceptance and adaptation of cross-culture. For statistical hypothesis testing, it conducts a questionnaire survey targeting mixed manning ships and examines empirically the inter-variables relation through the regression. The result of empirical research is that the group cohesiveness, job satisfaction and organizational commitment in the ship organization of Korean master(chief engineer) and foreign officers is higher than that of Korean master and officers. Moreover, it is found that the group cohesiveness of 31~50% foreign crew group is less than that of the others. However, There is no moderating effects of the acceptance and adaptation of cross-culture. Additionally, it demonstrates the higher job satisfaction and organizational commitment in the stronger cohesiveness groups. The finding suggests the rationale that shipping and ship management companies could raise the group cohesiveness, job satisfaction and organizational commitment by moderating the type of mixed manning and the ratio of foreign crew.

• Journal of Pharmacopuncture
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• v.7 no.1 s.12
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• pp.87-100
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• 2004

Objective : This research was performed to investigate the effect of herbal acupuncture(Atratylodes japonica, Coix lachrymajobi, Ephedra sinica, Atratylodes japonica mixed with Coix lachrymajobi and Ephedra sinica mixed with Green tea) at Pungnyung(ST40) and Umnungchon(SP9) on weight gain, food intake, food efficiency, serum of lipid concentrations, liver function and HDL to total cholesterol ratio of rats fed high fat diet for 5weeks. Method : Experimental groups were divided into normal group(Normal), high fat diet group(Control), high fat diet and Atractylodes japonica-herbal acupuncture group(AJ), high fat diet and Coix lachrymajobi-herbal acupuncture group(CL), high fat diet and Ephedra sinica-herbaI acupuncture group(ES), high fat diet and Atractylodes japonica+Coix lachrymajobi-herbal acupuncture group(AJ+CL), Ephedra sinica+Green tea-herbal acupuncture group(ES+GT). Herbal acupuncture was bilaterally treated at the level of 132.5mg/kg body weight per 2day. Results : Body weight and food efficiency were decreased in AJ, ES, AJ+CL, ES+GT. The level of serum total cholesterol, triglyceride and free fatty acid were increased in AJ, ES, ES+GT. That of serum HDL-cholesterol was increased in AJ. The change of food intake, the level of serum phospholipid and ALP were not significant. The HDL to Total cholesterol ratio was increased in AJ and ES. Conclusion : Atractylodes japonica-herbal acupuncture in ST40 SP9 is effective on Body weight, food efficiency ratio, the level of serum lipid, protection of liver function and prevention cardiovascular risk by obesity induced by high fat diet. Herbal acupuncture mixed Ephedra sinica with Green tea can control the body weight, food efficiency ratio and the level of serum lipid.