The purpose of this study intends to development of a lap scale 1-ton standard combustion chamber. The manufactured standard combustion chamber analyzes pilot combustion tests and emission standard data of MGO fuel oil. The actual capacity of the standard combustion chamber is about 900L, total weight of 265kg. As a result of the pilot combustion test, the O2 was about 8.01% and the CO2 was about 9.34%. In the case of NOx, it was about 33.50 ppm, and SOx (SO2) was about 0.76ppm. The combustion efficiency was about 72.41%, the exhaust gas temperature was 366.7℃, and the combustion chamber internal temperature was about 448.0℃.

This study intends to use the possibility of an eco-friendly alternative fuel to be applied to ships as a sample manufacturing method for ship MGO and bioethanol mixed fuel oil as basic evidence. The components of the manufactured mixed fuel oil were analyzed using the ISO-8217 standard testing method. As a result of analysis showed that in the lower calorific value decreased to 43030J/g at BE0 fuel and 37010J/g at BE30 fuel. The high calorific value decreased to 46.065MJ/kg at BE0 fuel and 39.460MJ/kg at BE30 fuel. The density decreased to 840.8kg/m3 at BE0 fuel and 837.0kg/m3 at BE30 fuel. In the case of flash point it was 67.5℃ when BE0, and decreased to less than 40.0℃ when BE10 to BE30. Finally the Kinematic Viscosity was 3.011mm2/s at BE0 and decreased to 2.502mm2/s at BE30.

We report on stretchable electrochromic films of poly(3-hexylthiophene) (P3HT) fabricated on silver nanowire (AgNW) electrodes. AgNWs electrodes are prepared on polydimethylsiloxane (PDMS) substrates using a spray coater for stretchable electrochromic applications. On top of the AgNW electrode, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is introduced to ensure a stable resistance over the electrode under broad strain range by effectively suppressing the protrusion of AgNWs from PDMS. This bilayer electrode exhibits a high performance as a stretchable substrate in terms of sheet resistance increment by a factor of 1.6, tensile strain change to 40%, and stretching cycles to 100 cycles. Furthermore, P3HT film spin-coated on the bilayer electrode shows a stable electrochromic coloration within an applied voltage, with a color contrast of 28.6%, response time of 4-5 sec, and a coloration efficiency of 91.0 cm2/C. These findings indicate that AgNWs/PEDOT:PSS bilayer on PDMS substrate electrode is highly suitable for transparent and stretchable electrochromic devices.

The role of Fatty acid binding protein 4 (FABP4) gene is critical for lipid metabolism and for maintaining homeostasis in adipocytes. Association between Hanwoo carcass traits and FABP4 gene g.7516G>C SNP has been reported previously, however, its association and how does it influence Korean brindle and black cattle has not been demonstrated and established till date. For this purpose, the study was planned to analyze the SNP association (Single Nucleotide Polymorphism) (g.7516G>C) in FABP4 gene and gather genetic information on economic traits of Korean brindle cattle and black cattle. As per sequence of bovine FABP4 gene available (Genbank accession No. NC_007312.4), one pair of primers (5’-ATA TAG TCC ATA GGG TGG CAA AGA-3’ and 5’-AAC CTC TCT TTG AAT TCT CCA TTC T-3’) was designed to amplify a 452bp product of the FABP4 gene including the region of 7417–7868. The SNP, detected by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) methods using restriction enzyme MspA1I, was genotyped in 117 animals of brindle cattle and 24 animals of black cattle population. Statistical analysis revealed that the FABP4 genotype significantly (p<0.05) affect with carcass weight, but there was no significant association with any other economic traits was observed in brindle as well as in black cattle. In conclusion, these results suggested that SNP (g.7516G>C), located in FABP4 gene, could be used as important DNA marker of economic traits in Korean brindle cattle. Furthermore, we suggest that additional samples needs to further analysed to make related data exclusively authentic.

The melanocortin receptor type 4 (MC4R) gene is expressed in the hypothalamus and regulates energy intake and body weight. Recently, it has been reported that obesity and energy balance in human were also regulated by the MC4R gene. Therefore the objective of this study was to identify the polymorphism on the MC4R gene SNP C1786T and its association with economic traits in Korean native cattle (brindle and black cattle) by PCR-RFLP. A total of 125 cattle from the two breeds were tested for economic traits (meat quality index, backfat, thickness, carcass weight, longissimus muscle area and marbling score) and data was analyzed using SAS program. In the results, C allele had highest frequency than G allele frequency in the both breeds and the gene was significantly associated with meat quantity index and backfat thickness in brindle cattle breed. However, in black cattle, the gene was significantly associated with longissimus muscle area (p<0.05). These results suggest that C1786T SNP of the MC4R gene may be useful as a genetic marker for economic traits in the brindle and black cattle.

Heat transfer performance improvement by fin and groovs is studied for condensation of R-11 on integral-fin tubes. Eight tubes with trapczodially shaped integral-fins having fin density from 748 to 1654fpm(fin per meter) and 10, 30 grooves are tested. A plain tube having the same diameter as the finned tubes is also used for comparison. R-11 condensates at saturation state of 32 ℃ on the outside tube surface coded by inside water flow. All of test data are taken at steady state. The heat transfer loop is used for testing singe long tubes and cooling is pumped from a storage tank through filters and folwmeters to the horizontal test section where it is heated by steam condensing on the outside of the tubes. The pressure drop across the test section is measured by menas pressure gauge and manometer. The results obtained in this study is as follows : 1. Based on inside diameter and nominal inside area, overall heat transfer coefficients of finned tube are enhanced up to 1.6 ~ 3.7 times that of a plain tube at a constant Reynolds number. 2. Friction factors are up to 1.6 ~ 2.1 times those of plain tubes. 3. The constant pumping power ratio for the low integral-fin tubes increase directly with the effective area to the nominal area ratio, and with the effective area diameter ratio. 4. A tube having a fin density of 1299fpm and 30 grooves has the best heat transfer performance.