• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.307-313
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• 2002

In the paper, the prototype development of a 75kW class microturbine for the distributed generation market is partly presented which has continued with the government funding. In the introduction, an overview of the development of microturbines in the world is presented. A series of development procedures are shown with design, manufacture and self-sustaining tests. During the first year, aerodynamic and structural design/analysis, mechanical design are performed for the compressor, the turbine and the combustor. A premixed lean burn combustor technology is used fur the low emission requirements. Foil air bearings and high-speed motors are employed for higher reliability. The self-sustaining conditions have been successfully achieved with the prototype manufactured engine as a preceding operation.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.91-96
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• 2000

A commercial-scale Fluidized Bed Incinerator(FBI) to treat dewatered sludges has been developed by Jindo Corporation, Korea, as one of the governmental R&D project during 1990 to 1997. The FBI plant was constructed at Kunsan city and fully in operation after finishing the successful test-burn period since June 1998. The company now has a capability of the design, construction and operation of commercial FBI plants. This paper introduces the experiences of design and operation of Kunsan FBI plant, which has the capacity of 60 ton/day and incinerates various sludges from waste water treatment facilities and liquid waste such as waste oil or waste solvent.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.1
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• pp.31-38
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• 2016

Since the oil shock of 1970's there was a strong upward tendency for the use of the high viscosity and poorer quality fuels. Therefore the misfiring engine occurs due to the decrease of quantity injected for lean burn and emission control in Compression Ignition Common Rail Direct Injection diesel engine. In this study, it is designed and used the test bed which is installed with fuel injector controller. In addition to equipped engine using CRDI by controlling the injection timing with mapping modulator, it has tested and analyzed the engine performance and combustion characteristics, as it is varied that they are the operating parameters: fuel injected quantity, engine speed and injection timing.

• Polymer(Korea)
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• v.25 no.3
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• pp.391-398
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• 2001

Two-component polyurethane (PU) flame-retardant coatings were prepared by blending tribromo modified polyesters ($TBAO_s$) and isocyanate.$TBAO_s$ were synthesized by condensation polymerization of tribromoacetic acid, a flame-retardant component, with 1,4-butanediol, adipic acid, and trimethylolpropane. The content of tribromoacetic acid was varied by 10, 20, and 30 wt% for the reaction. Various physical properties of these new flame-retardant coatings were comparable to nonflame-retardant coatings. Coatings with 20 wt% tribromoacetic acid did not burn during the vertical burning test.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.242-247
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• 2003

An experimental study presents characteristics of combustion in a combustion chamber by port deactivation valve for economy and emissions standards. In order to use combustion properties data it is necessary to build some data base, which use cylinder pressure sensor, etc. Port deactivation valve has been developed to satisfy requirement of achieving sufficient swirl generation to improve the combustion. A feasibility and necessity of combustion pressure based cylinder spark timing control has been examined. So, this was obtained the Coefficient of Variation(COV) and the mass-burned(MFB). The characteristics of pressure ratio fraction is similar to that of mass-burned fraction. Using the results of the test, the effects of the combustion chamber can be improved combustion stability by port deactivation.

• Animal cells and systems
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• v.10 no.1
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• pp.21-25
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• 2006

In the present study, Dravya-an organic compound used for seed treatment along with the common fungicides to test its compatibility in the management of Alternaria padwickii in paddy. Dravya (a sea weed extract) was found highly compatible with fungicides like Bavistin and Dithane M-45. Incidence of Alternaria padwickii and Bipolaris oryzae was also reduced to a greater extent in the paddy seed samples of Dravya treatment. On the other hand, it also enhanced the seed germination and seedling vigour. Seedlings of treated samples also showed enhanced activity of peroxidase upon challenge inoculation with Alternaria padwickii. The enzyme activity in the seedlings challenged with the pathogen was two fold more over control. The suppression in disease incidence in growing plants indicated the promising effect of Dravya and Dithane M-45 under green- house conditions.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.603-606
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• 2004

본 연구는 반도체 검사공정 중의 하나인 MBT 공정의 Rework 투입정책에 관한 연구이다. MBT 공정에서는 제품의 신뢰성과는 상관없이 설비오류로 인한 불량품이 다량으로 발생한다. 이러한 불량품을 MBT 공정의 재검사 작업인 Rework을 통해 양품으로 전환하게 된다. MBT 공정의 Rework은 FAB 공정 이후의 많은 공정을 거치지 않고 단일공정 진행으로 새로운 양품을 얻을 수 있는 이점을 가진다. 반면에 Rework 비용 및 공정재고비용이 발생하는 특징이 있다. 현재 MBT 공정의 Rework 작업은 정해진 규칙 없이 작업자 경험에 의존하여 진행하며, 제품의 중요도 및 재고량에 따라 투입이 정해진다. 또한 주문 작업의 투입일정과 납기를 고려하지 않은 Rework 작업으로 인해 납기차질이 발생하기도 한다. 본 연구에서는 Rework 작업이 생산계획에 영향을 주지 않는 범위 안에서의 투입계획을 제안한다. 또한 MBT 공정의 Rework 이익인 제조원가 절감이익과 비용인 Rework 비용, 재고비용을 고려한 Rework 제품 투입정책을 제안한다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.440-447
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• 2001

This study investigate experimentally the effect of in height, thickness, and clearance on the boiling heat transfer. The heat surfaces having copper fin array is tested for pool boiling. The gas-liquid exchange interference is investigated based on fin array clearance. These test results can be applied to the design of tube bundle system. The fin height of 2 mm is found to be effective. Effects of heat transfer promotion reaches the highest level when the fin clearance is 0.5mm. Also, heat flux is increased when the fin thickness is smaller. But0.2 mm fin thickness is highly recommended.

• Journal of ILASS-Korea
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• v.23 no.2
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• pp.96-101
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• 2018

The purpose of this study is to investigate the effect of water injection on combustion characteristics of gasoline direct injection (GDI) engine with turbo-charger under low-load operating condition. The test engine used in this study has four-cylinder and 10.2 of compression ratio. In order to study the effect of water injection ratio on combustion characteristics, the water was injected into the intake port from 10% to 50%, based on fuel injection quantity. From the experiment, it revealed that the water injection induced the improvement of fuel economy because of the advance of spark-timing by the reduction of in-cylinder temperature. In addition, the water injection caused the prolong of extension of the ignition delay and slight increase of burn duration.

• Journal of Life Science
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• v.10 no.2
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• pp.157-163
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• 2000

One hundred eight strains of Pseudomonas aeruginosa isolated from the patients (sputum, urine, burn skin, stool and blood) of Pusan National University hospital were tested for exonezyme production, antimicrobial susceptibility and serotyping. The results obtained were as follow: In exonezyme production test, 50 strains (46.30%) produced both protease and elastase. Thirty three strains (30.55%) did not produce any exoenzyme, 18 strains (16.67%) produced only protease and 7(6.48%) stains only produced elastase. As the result of antimicrobial susceptibility by the disc diffusion method, most strains were resistant to sulfamethoxazole (96.30%). But the resistant rate against gentamicin and ticarcillin were 47.23% and 46.30% respectively. The resistant rate to other antibiotics were less than 40%. All strains could be serologically typed. Most strains were identified as type Ⅲ: among them, 51 strains were belonged to serotype E. The correlation of serotype and exoenzyme production was not found.