• Journal of ILASS-Korea
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• v.11 no.1
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• pp.30-38
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• 2006

High temperature furnaces such as power plant and incinerator contribute considerable part of NOx generation and face urgent demand of De-NOx system. Reducing agent is injected into the flue gas flow to activate do-NOx system. Almost SCR system adopt vaporized ammonia injection system. Vaporizer, dilution system and additional space are needed to gasify and inject ammonia. Liquid spray injection system can simplify and economize post-treatment system of flue gas. In this study, mixing caused by gas or liquid injection of reducing agent into flue gas duct was investigated experimentally. Carbonated water was used as tracer and simulated agent and mixing of liquid spray in a duct flow was studied. To achieve that, the angle of attack of static mixer is simulated and $CO_2$ concentration is measured.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.2
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• pp.269-276
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• 2004

A marine diesel engine should realize optimal efficiency operation while reducing NOx. Fuel injection systems by electronic control can become effective means for that. Although it would be able to get more precise engine control compared to the mechanical injection system, it needs some accurate and instant information in order to bring its ability into full play while sailing on the sea. Very important information of them is shaft torque and continuous combustion pressure of all cylinders. The system presented in this report can deliver those data.

• Journal of Embryo Transfer
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• v.9 no.2
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• pp.167-172
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• 1994

This experiment was arried out to investigate the development of ea4y rabbit embryos in vivo. Twenty-six New Zealand White does were superovulated by treatment with PMSG(Intervet Co; I. M single injection, 150. U./rabbit) followed 3 day later by simultaneous I.V injection of 100 I.U HCG (Intervet Co, )and natural service with fertile male. All of does was killed at the specific times (24, 27, 30, 36, 42, 50 and 93 h post-hCG) to find out the early embryonic development in vivo respectively. Embryos at the specified stages of development were obtained at the following times after injection of hCG; one-ceH at 24 h, two-cell at 24~27h, four-cell at 27~36 h, morulae at 50 h and early blasto-cyst at 93 h and expanded or hatching blastocyst at 144 h. Number of embryos recovered per rabbit superovulated was 26.1 and average of recovery rate was 83.7%. The results suggest that superovulation was efficient for the increase of embryo number in rabbits, and as shown in results, asynchronous cleavage was prevalent among the recovered embryos.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.5
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• pp.209-214
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• 2016

Foam reaction injection molding (FRIM) is a widely used process for manufacturing polyurethane foam with complex shapes. Numerical model for polyurethane foam forming reaction during FRIM process has been intensively investigated by a number of researchers to precisely predict final shapes of polyurethane foams. In this study, we have identified a problem related with a previous theoretical model for polyurethane foam forming reaction. Thus, previous theoretical model was modified based on experimental and computational results.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.36-37
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• 2006

This study aims to investigate the usage of nano-scale particles in a micro metal injection molding ($\mu$-MIM) process. Nanoscale particle is effective to improve transcription and surface roughness in small structure. Moreover, the effects of hybrid micro/nano particles, Cu/Cu and SUS/Cu were investigated. Small dumbbell specimens were produced using various feedstocks prepared by changing binder content and fraction of nano-scale Cu particle (0.3 and $0.13{\mu}m$ in particle size). The effects of adding the fraction of nano-scale Cu powder on the melt viscosity of the feedstock, microstructure, density and tensile strength of sintered parts were discussed.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.93-94
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• 2006

A novel production method for porous metal components has been developed by applying powder space holder (PSH) method to metal powder injection molding (MIM) process. The PSH-MIM method has an industrial competitive advantage that is capable of net-shape manufacturing the micro-sized porous metal products with complicated shapes and controlled porosity and pore size. In this study, the small impeller with homogeneous micro-porous structure was manufactured by the PSH-MIM method. The effects of combinations in size and fraction of PMMA particle on dimensional tolerance and variation of sintered porous specimens were investigated. It was concluded that the PSH-MIM method could manufacture commercially microporous metal components with high dimensional accuracy.

• Journal of the Korean Society of Systems Engineering
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• v.17 no.2
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• pp.1-8
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• 2021

This study proposes a systems engineering approach for the development of an advanced planning & scheduling (APS) system for a cosmetic case manufacturing factory. The APS system makes production plans and schedules based on the injection process, which consists of 27 plastic injection machines in parallel to control recommended inventory of products. The system uses machine operation/failure information and defective product/work-in-process tracking information to support intelligent scheduling. Furthermore, a genetic algorithm model is applied to handle the complexity of heuristic rules and machine/quality constraints in this process. As a result of the development, the recommended inventory compliance rate is improved by scheduling the 30-day production plan for 15 main products.

• Journal of Environmental Science International
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• v.32 no.7
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• pp.483-492
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• 2023

In this study, the treatment of livestock wastewater using an aerobic granular sludge based sequencing batch reactor was investigated. The reactor operation was carried out by general injection and split injection methods. The average removal efficiency of organic matter after the adaptation period was 71.5 and 87.4%, respectively. Some untreated organic matter was attributed to recalcitrant organic matter. The average removal efficiency of total nitrogen was 65.6 and 88.4%, respectively. These results indicate that the denitrification reaction by split injection was carried out smoothly. As for the solids, the ratio of aerobic granular sludge/mixed liquor suspended solid can be determined as the main factor of the process operation, and the ratio increased gradually and finally reached 86.0%. Correspondingly, the sludge volume index (SVI) was also improved, reaching 54 mL/g at the end of operation, and it is believed that the application of a short settling time contributed to the improvement of settleability.

• Journal of ILASS-Korea
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• v.29 no.1
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• pp.7-15
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• 2024

This study investigates the performance of 2.0L hybrid vehicles equipped with Liquefied Petroleum Gas (LPG) fuel engines, using energy flow analysis. By incorporating a direct LPG injection system (LPDi), the research aims to overcome the reduced maximum output commonly associated with LPG engines. Moreover, the integration of a hybrid system is explored as a means to enhance vehicle fuel economy while reducing CO₂ and emissions. The study employs data from FTP-75 and HWFET driving cycle to inform future research efforts focused on predicting CO₂ emissions and fuel economy for Hybrid Electric Vehicles utilizing LPG Direct Injection. The findings offer insights into optimizing fuel systems for better environmental and operational performance in hybrid vehicles.

• Clean Technology
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• v.14 no.1
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• pp.1-6
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• 2008

Removal of paraffin wax from a ceramic injection mold using supercritical $CO_2$ has been studied. The paraffin wax is used as a binder in the ceramic injection molding process. The effects of pressure, temperature and flow rate of supercritical $CO_2$ on the removal of the paraffin wax were investigated. The removal rates were measured with various flow rates of $CO_2$ in the range of 328.15 - 348.15 K and 15 - 30 MPa. The removal rate of paraffin wax increased as the pressure increased. In the effect of temperature, the paraffin wax was effectively removed over 329.15K (melting point of paraffin wax), however, the efffct of temperature was not significant when the temperature was further increased. The increase of $CO_2$ flow rate also affected the removal of paraffin wax. However, the effect of flow rate was not observed when the flow rate reached a certain value. Propane was used as a co solvent in order to remove the paraffin wax effectively. When the propane was added to the $CO_2$, the removal efficiency was improved. The paraffin wax was completely removed from the ceramic injection mold without any change in their shape and the structure.