• Journal of Marine Life Science
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• v.7 no.2
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• pp.163-170
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• 2022

In this study, the results of hybridization were evaluated by analyzing the biomarkers of Haliotis discus hannai and hybrid abalone (H. madaka♀^*H. discus discus♂) in marine net cage. The survival rate was similar both experimental groups, but the growth (shell length) was about 10% faster in hybrid abalone. The deformity of respiratory pore in the hybrid abalone was about 6% lower than H. discus hannai, and the shell depression was about 15% lower in the hybrid abalone. In the biochemical composition, crude protein was about 3.1% higher in hybrid abalone, and showed similar values except for the crude protein. In the histological structure of the hepatopancreas, which performs the functions of digestion, absorption and detoxification of abalone, good results were obtained in the hybrid abalone. On these results, it is judged that the hybrid abalone will have high aquaculture productivity in the aquaculture environment.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1754-1759
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• 2002

A study was carried out to investigate the nutritive value and utilization of hybrid sorghum and perennial grass species viz. setaria (Setaria anceps) and hybrid napier when intercropped with soybean by growing Jersey crossbred heifers. Fifteen growing crossbred heifers (Jersey${\times}$Red Sindhi) of between 7-10 months age and pre-trial average body weight of 49-50 kg were divided on the basis of weight in to three treatment groups viz. $T_1$-hybrid sorghum+soybean, $T_2$-setaria+soybean and $T_3$-hybrid napier+soybean in a completely randomized block design. Intercropped forages were harvested fresh, chaffed and mixed before they were offered to the heifers. Chemical composition of the herbage, dry matter intake (DMI), body weight gain and nutrient digestibility co-efficients were estimated. The herbage mixtures had crude protein (CP) content in the range of 11.87 to 13.86% and ether extract (EE) contents were 2.91 to 3.11%, respectively. The herbage mixtures were rich in minerals (ash). The gross energy (kcal/g DM) was higher in hybrid napier+soybean, while hybrid sorghum+soybean and setaria+soybean herbage mixtures had lower value for gross energy. The hybrid sorghum+soybean and setaria+soybean herbage mixtures had higher contents of NDF, ADF, cellulose, lignin and silica as compared to that of hybrid napier+soybean herbage mixture. The heifers fed hybrid napier+soybean herbage mixture had significantly (p<0.05) higher $DMI\;g/kg\;W^{0.75}$ ($97.41{\pm}4.34$) as compared to hybrid sorghum+soybean ($88.31{\pm}2.66$) and setaria+soybean ($79.29{\pm}1.06$) herbage mixtures. Nutrients digestibility, DCP percent, DCP intake and nitrogen balance were significantly (p<0.05) higher in the heifers fed on hybrid napier+soybean herbage mixture. There was a significant (p<0.05) difference among different herbage mixtures in TDN. The heifers on setaria+soybean herbage mixture had lower average body weight gain (g/day) than those on hybrid sorghum+soybean and hybrid napier+soybean herbage mixtures. Data obtained in this experiment demonstrated that herbage mixture of hybrid napier+soybean was better than hybrid sorghum+soybean and setaria+soybean herbage mixtures in the nutrition of growing heifers. It had highest nutritive value, better digestibility co-efficients which showed better growth rate and higher feed efficiency. In ranking, hybrid napier+soybean herbage mixture was better followed by hybrid sorghum+soybean and setaria+soybean in nutritive value in the parameters studied. For future wasteland development program in humid-sub tropics of Himachal Pradesh hybrid napier and its intercropping with soybean is recommended for general adoption because of its better adaptability and higher nutritive value.

• Advances in aircraft and spacecraft science
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• v.4 no.3
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• pp.281-296
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• 2017

The axial-injection end-burning hybrid rocket proposed twenty years ago by the authors recently recaptured the attention of researchers for its virtues such as no ${\zeta}$ (oxidizer to fuel mass ratio) shift during firing and good throttling characteristics. This paper is the first report verifying these virtues using a laboratory scale motor. There are several requirements for realizing this type of hybrid rocket: 1) high fuel filling rate for obtaining an optimal ${\zeta}$; 2) small port intervals for increasing port merging rate; 3) ports arrayed across the entire fuel section. Because these requirements could not be satisfied by common manufacturing methods, no previous researchers have conducted experiments with this kind of hybrid rocket. Recent advances in high accuracy 3D printing now allow for fuel to be produced that meets these three requirements. The fuel grains used in this study were produced by a high precision light polymerized 3D printer. Each grain consisted of an array of 0.3 mm diameter ports for a fuel filling rate of 98% .The authors conducted several firing tests with various oxidizer mass flow rates and chamber pressures, and analysed the results, including ${\zeta}$ history, using a new reconstruction technique. The results show that ${\zeta}$ remains almost constant throughout tests of varying oxidizer mass flow rates, and that regression rate in the axial direction is a nearly linear function of chamber pressure with a pressure exponent of 0.996.

• Journal of Life Science
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• v.12 no.6
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• pp.740-744
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• 2002

This experiment was conducted to clarify the effects of physiological properties in culture media on the proliferation and the acclimation of bulblets of several kinds of lilies cultured in vitro. Proliferation rate of bulblets from bulblet of Oriental hybrid ‘Marco Polo’, ‘Casa Blanca’ and Asiatic hybrid ‘Jolanda’ was higher in solid MS media compared with bulblets from scale Acclimation rate of regenerated bulblets was high in solid media which was pre-cultured in vitro, compared with liquid media. Sprouting rate of bulblets from bulblet was higher than bulblets from scale.

• Journal of the Korean Society of Propulsion Engineers
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• v.1 no.2
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• pp.58-66
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• 1997

To investigate the effect of the oxidizer mass flow rate on the fuel regression rate of the hybrid rocket, a laboratory size rocket was designed and ground fire test were carried out. Oxidizer was gaseous oxygen and HTPB was used as a fuel. Following correlation was obtained from the experiment. $\dot{r}$=$0.183G_o^{0.605}$

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.261-264
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• 2008

This study experimentally examines combustion characteristics of a hybrid rocket in which solid paraffin is used as a fuel, while oxidizer is pure oxygen. Especially, the experiment investigates the effects of chamber pressure and configuration of fuel grain. The pressure inside the combustion chamber is varied by changing a flow rate of oxidizer. The regression rate is observed to increase as the chamber pressure does. There also exists the effects of shape of fuel grain on thrust. Characteristic of paraffin hybrid rocket changes with shape of fuel grain. When there is a room near the injector, thrust increases. On the other hand, the room near the nozzle does not contribute to thrust increasement.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.247-250
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• 2008

An experimental investigation was conducted to clarify the combustion characteristics and merge characteristics of PMMA-GOX and PE-GOX hybrid motor using multi-port fuel grain configuration. The regression rate of multi-port fuel grain is higher than the regression rate of single-port fuel grain by thermal conduction and chamber pressure. The merge of multi-port has an effect on hybrid rocket performance by change of a combustion area.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.205-205
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• 2022

Sorghum (Sorghum bicolor L.) is a major cereal grain crop of the world and It can be cultivated under high temperature and dry condition with high adaptability to the adverse environment. It is usually eaten with rice in korea and most of domestic sorghum cultivars have been developed by pure line selection and cross breeding. In prior studies, Hybrid cultivar (F1 seed) was known to improve 30-40% in yield and resist to disease and pest than pure line varieties due to hybrid vigor. Therefore, study on the hybrid sorghum is continuously necessary. In korea, hybrid sorghum cultivar have been developed, so we need to find methods seed production technology for supply and commercialization of hybrid seed cultivar. Female inbred line(A-line) and male inbred line(R-line) are needed for hybrid seed production. This study was carried out to investigate growth characteristics and yield of hybrid sorghum according to the seedling period and planting rate between female inbred line(YSA1) and male inbred line (Sodamchal, Miryang 19). When the flowering period of two inbred groups in the process of hybrid seed production is coincides, hybrid seed production is increase. The female inbred line and male inbred lines were cultivated at Daegu in 2021. Two inbred lines were sown at intervals of 3 days and 7days and were evaluated flowering period. As a result, the flowering period of the female inbred line and male inbred lines were matched at the 7days interval. To find out optimal planting rate, two inbred lines were cultivated under different plating rate (4:2, 5:2, 6:2). Yield of YSA1/Sodamchal(F1) was the highest 130(kg/10a) in the 4:2 ratio and yield of YSA1/Miryang 19 was the highest quantity of 139(kg/10a) in the 6:2 ratio. The results of this study could be helpful for hybrid Sorghum seeds production.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.1
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• pp.55-62
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• 2004

Although the previous researches evaluated the fatigue behavior of glass fiber/epoxy laminates using the traditional fracture mechanism, their researches were not sufficient to do it: the damage zone of glass fiber/epoxy laminates was occurred at the delamination zone instead of the crack-metallic damages. Thus, previous researches were not applicable to the fatigue behavior of glass fiber/epoxy laminates. The major purpose of this study was to evaluate delamination behavior using the relationship between crack length and delamination width in hybrid composite material such as Al/GFRP laminate. The details of investigation were as follows : 1) Relationship between crack length and delamination width, 2) Relationship between delamination aspect ratio and delamination area rate, 3) Variation of delamination growth rate is attendant on delamination shape factors. The test results indicated that the delamination growth rate depends on delamination width delamination aspect ratio and delamination shape factors.

• Journal of the Korean Mathematical Society
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• v.57 no.5
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• pp.1167-1186
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• 2020

This paper considers the case of pricing discretely-sampled variance swaps under the class of equity-interest rate hybridization. Our modeling framework consists of the equity which follows the dynamics of the Heston stochastic volatility model, and the stochastic interest rate is driven by the Cox-Ingersoll-Ross (CIR) process with full correlation structure imposed among the state variables. This full correlation structure possesses the limitation to have fully analytical pricing formula for hybrid models of variance swaps, due to the non-affinity property embedded in the model itself. We address this issue by obtaining an efficient semi-closed form pricing formula of variance swaps for an approximation of the hybrid model via the derivation of characteristic functions. Subsequently, we implement numerical experiments to evaluate the accuracy of our pricing formula. Our findings confirm that the impact of the correlation between the underlying and the interest rate is significant for pricing discretely-sampled variance swaps.