• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.21 no.6
• /
• pp.569-574
• /
• 2008

In the device structure of ITO/tris(8-hydroxyquinoline) aluminum ($Alq_3$)/Al device, we investigated the efficiency improvement of organic light-emitting diodes (OLEDs) depending on the hole-size of crucible boat. The device was manufactured using a thermal evaporation under the base pressure of $5{\times}10^{-6}\;Torr$. The $Alq_3$ organics were evaporated to be 100 nm thick at a deposition rate of $1.5\AA/s$, and in order to investigate the optimal surface roughness of $Alq_3$, the $Alq_3$ was thermally evaporated to be 0.8 mm, 1.0 mm, and 1.5 mm as a hole-size of the boat, respectively. We found that luminance and external quantum efficiency are superior when the hole-size of the boat is 1.0 mm. The external quantum efficiency of the device made with the hole-size of 1.0 mm boat were improved by a factor of ten compared to the devices made with the hole-size of non boat.

• The Journal of Fisheries Business Administration
• /
• v.42 no.2
• /
• pp.31-45
• /
• 2011

Costal fisheries use small boat. The boats are frequently substituted with newly made boat or proper boat. When the boat which is substituted with another one after the fixed date for compensation is estimated for fisheries loss by public project, it is matter that which boat is the object for estimating average catch of fish. There are three ways in practical business. They are based on the date of spot probe, the date of conference for compensation and fixed date for compensation. In case of applying the first and the second ways, as the object of compensation is not fixed, there is problem that estimated result can be changed depending on changing boat tons even after the date of spot probe and the fixed date for compensation. Most of all, these ways are against Attached Form No.4 of the Enforcement Ordinance of Fisheries Law which regulate to calculate average catch of fish applying result of fishery for retroactively counted 3 years from the year before the year in which administrative measure day is. The other side, in applying boat tons based on the fixed date for compensation, estimated result of compensation will not change even boat substituted after the fixed date for compensation. Even though applying tons based on the fixed date for compensation, a problem still remains. If the boat get bigger after the fixed date for compensation, the then boat size must be applied for calculating average catch. But the boat get smaller, the changed boat size must be applied. Because changed small boat would be damaged less than the previous boat. And decrease in catch by changing boat into small one is not due to the project but due to the personal responsibility. This will help to increase objectivity and reliance on the compensation result. As the other objects are fixed based on the fixed date for compensation in the Act on Acquisition and Compensation of Land and Others for Public Project, it can be balanced with other object.

• Transactions on Electrical and Electronic Materials
• /
• v.9 no.3
• /
• pp.105-109
• /
• 2008

Electrical characteristics of organic light-emitting diodes were investigated by varying a hole-size in evaporation boat in the device structure of ITO/tris(8-hydroxyquinoline) aluminum$(Alq_3)$/Al. The device was manufactured using a thermal evaporation under a base pressure of $5{\times}10^{-6}$ Torr. The $Alq_3$ emitting organics were evaporated to be a thickness of 100 nm at a deposition rate of $1.5{\AA}/s$. A cylindrical-shaped evaporation boat was made out of stainless steel with a small size of hole on top of the boat. Several evaporation boats were made having a different hole size on top; 0.8 mm, 1.0 mm, 1.5 mm, and 3.0 mm. We found that when the hole size on top of the evaporation boat is 1.0 mm, the average roughness is rather smoother compared to the other ones. Also, luminance and external quantum efficiency are superior to the others. Compared to the ones from the devices made with the hole-size of 0.8 mm boat. The luminance and external quantum efficiency of the device made with the hole-size of 1.0 mm boat were improved by a factor of seventy and thirty three, respectively. Also operating voltage is reduced to 2 V.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.11a
• /
• pp.29-30
• /
• 2007

In a device structure of ITO/tris(8-hydroxyquinoline) aluminum $(Alq_3)$/Al device, We investigated an the electrical characteristics of Organic Light-Emitting Diodes (OLEDs) depending on the hole-size of boat. The device was manufactured using a thermal evaporation under a base pressure of $5{\times}10^{-6}$ [Torr]. The $Alq_3$ organics were evaporated to be 100 [nm] thick at a deposition rate of $1.5[{\AA}/s]$, and in order to investigate the optimal surface roughness of $Alq_3$, the $Alq_3$ was thermally evaporated to be 0.8 [mm], 1.0 [mm], 1.5 [mm], and 3.0 [mm] as a hole-size of the boat respectively. We found that when the hole-size of the boat is 1.0 [mm], luminance and external quantum efficiency are superior.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.06a
• /
• pp.34-35
• /
• 2009

We have studied the electrical and optical of organic light-emitting diodes depending on hole size of crucible boat using BCP materials. The thickness of TPD, $Alq_3$ and BCP was manufactured 40 nm, 60 nm and 5 nm under a base pressure of $5\times10^{-6}$ Torr using at thermal evaporation, respectively. In order to investigate the optimal surface roughness of BCP, the BCP was thermally evaporated to be 0.8 nun, 1.0 mm, 1.2 mm and 1.5 mm as a hole size of crucible boat, respectively. As the experimental results, we found that the luminous efficiency and the external quantum efficiency of the device is superior to others when hole size of crucible boat using BCP is 1.2 mm. Also, compared to the ones from the devices having the hole size of crucible boat is 1.0 mm and 1.5mm layer, the external quantum efficiency were improved by 2.5 and 2.4 times.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.60 no.3
• /
• pp.207-216
• /
• 2024

This study conducted a marine experiment to improve the fishing system using miniaturized nets for anchovy boat seine to reduce the fleet size. As a result, the miniaturized net for anchovy boat seine properly opened the entrance of the bag net using the buoyancy of the flotation for position indication and the setting force of the ground rope without operating a separate fish detecting boat by attaching a large flotation at the entrances of the inside wing net and the bag net. This also enabled an operation type where the entrance of the bag net is confirmed using a flotation for position indication from a netting boat. The time and the number of people used for net casting and net hauling in the marine experiment were average of five minutes and 25-30 minutes, respectively, and 23-30 people for the existent net, while for the miniaturized large-scale net were average of three minutes and 23-25 minutes, respectively, and 19-25 people. This indicates that the operation time was shortened, the number of fish detecting boats was reduced by one boat, and the number of people for fishing work was decreased by four or five people due to the improvement of fishing operation system according to the reduction of fishing net size. As a result of measuring the shaft horsepower during net towing, the maximum net towing horsepower was 250 HP in comparison to the maximum RPM of the engine (1,200 RPM), indicating that the legal horsepower of 250 HP is enough to conduct net towing and the competitiveness of fishing using the net for anchovy boat seine is ensured through operation cost reduction.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.35 no.1
• /
• pp.1-7
• /
• 1986

The GaAs bulk single crystals are grown by the Horizontal Bridgman method. During the growth, one of the problems in Bridgman method is the boat wetting between GaAs molten and silica boat. This boat wetting may result in another nucleation to form twin crystals. In this study, We find that the optimal size for sand blasting is 320 mesh. Backfilling the ampoule with argon gas during the vaccum bake-out decreaes the boat wetting. The reaction mechanism of Ga with quartz to produce suboxide, Ga2O, and sillion is discussed.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.21 no.7
• /
• pp.609-614
• /
• 2011

The ship working environment of combat service support boat is much inferior to the ground working environment. For this reason, the crew of a combat service support boat suffer from an occupational disease such as hardness of hearing. Owing to its small size and low status, the improvement of its working and residential environment was occasionally ignored and its indoor noise was not fully investigated. In this study, for improving its residential environment indoor, the indoor noise of its shipboard compartments was analysed. These studies define the indoor noise level of combat service support boat is very high and some of indoor noise is exceeded the criteria for ship noise. Compared with marine police vessels, the indoor noise levels of marine police vessels are higher than the level of combat service support boat.

• Journal of Korea Ship Safrty Technology Authority
• /
• s.22
• /
• pp.34-53
• /
• 2007

In the case of hull material. large sized merchant ships are made of steel, on the other hand FRP or wood are used for small sized fishing boats. At present in Korea approximately 88,500 fishing boats are in operation of which 70% are made of FRP In the meantime, stainless steel is frequently used as shaft materials of the small-size FRP fishing boat. Namely, the kinds of shaft materials are STS 304(18Cr-8Ni), STS 316(18Cr-12Ni-2.5Mo steel) and STS 630(17Cr-Ni-Nb steel)etc. Among these things, STS 304 which is the cheapest and having ordinary corrosion resistance is most widely used as 2nd class shaft material. But, using STS 304 for shaft system material of the small-size FRP fishing boat on seawater environments entails a severe corrosion which causes shaft system troubles. Particularly, the corrosions tend to be concentrated of the stern and bow side, propeller shaft surface of inside of stern tube and the boat having no stern cooling pipe line system. As a solution for those problems, research on the ways to mitigate corrosion on the part of 2nd class stainless steel shaft have been undertaken. In the result, not only clarification for the reason of corrosion of the part of stainless steel shaft used mainly for the small-size FRP fishing boat was done, but also most optimal corrosion protection system was developed by experimenting shaft's protection simulation based of the electrochemical cathodic protection principle. In addition, verification through the field test on the optimal cathodic corrosion protection method by means of aluminum sacrificial anode was carried out. In this study, effective and economical shaft's protection system is suggested to the small-size FRP fishing boat operator by substantiating the results obtained from the research on the optimal cathodic protection.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.27 no.12
• /
• pp.1734-1743
• /
• 2003

Aerosol generator using an electrically heated tube furnace is a stable apparatus to supply nanometer sized aerosols by using the evaporation and condensation processes. Using this method, we can generate highly concentrated polydisperse aerosols with relatively narrow size distribution. In this work, characteristics of particle size distribution, generated from a tube furnace, were experimentally investigated. We evaluated effects of several operation parameters on particle generation: temperature in the tube furnace, air flow rates through the tube, size of boat containing solid sodium chloride(NaCl). As the temperature increased, the geometric mean diameter increased and the total number concentration also increased. Dilution with air affected the size distribution of the particles due to coagulation. A smaller sized boat, which has small surface area to contact with air, brings smaller particles of narrow size distribution in comparison of that of a larger boat. Finally, we changed the electrical mobility diameter of aggregate sodium chloride particles by varying relative humidity of dilution air, and obtained non-aggregate sodium chloride particles, which are easy to generate exact monodisperse particles.