• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.99-104
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• 2001

Slag product has the possibility as alternative aggregate and sand under the circumstance of natural resource shortage. Copper slag is the by-product produced in process of copper industry. Recycling the slag in construction industry could give positive effects on the environmental preservation. This study presents that the fundamental properties of high strength concrete which used copper slag as alternative sand. Testing factors are concrete's slump, bleeding, air contents and compressive strength. The results of this study are as follows. (1) Mixing of W/C 30%, substitution rate 25% shows the best slump. As substitution rates are going up, concrete slump is uprising and air contents are downsizing. (2) The bleeding of concrete becomes more serious as substitution rates are going up. (3) The best compressive strength of copper slag concrete is achieved in mixing of W/C 30%, substitution rate 25%.

• Korean Management Science Review
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• v.17 no.2
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• pp.97-113
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• 2000

The introduction of client server systems raises some serious IS control concerns. Although client server systems increase system flexibility and compatibility, and facilitates system downsizing and process restructuring, multiple operating systems, database management systems, and platforms of client-server system increase th potential exposures and risks of the system. It is needed to recommend the effective control framework to mitigate risks. This paper suggests risks and control framework for client server system. The results of two case studies indicate that program and database management are important as program and data should be located and maintained in client and servers. It becomes difficult to manage divided programs and data logic that are distributed across clients and servers that have different platforms. The case studies of two banks show that the extent of distribution of program and data logic affects the importance of program and database management controls.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.34-38
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• 2018

Recently, the turbo charger has become an important part because it yields little displacement and high power while downsizing the engine's fuel ratio for environmental purposes. In this study, flow analysis was conducted to form the basis of data regarding the best efficiency. The axial displacement was changed from none to 25 mm by controlling the configuration of the turbo charger and the flow analyses were compared with each other. The maximum rate of the outlet of model 1 was 46.36 m/s and the maximum pressure of model 4 was 0.761946 Pa. The maximum flow rate of model 4 was 0.000187650 kg/s. This study's result should aid in the effective design of a turbo charger with high performance.

• Journal of Contemporary Eastern Asia
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• v.11 no.1
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• pp.43-56
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• 2012

The paper chooses the "Asian Financial Crisis" as a case study to examine its impact on Malaysian economy and describes how Malaysian government responded to the crisis. It also focuses on the Asian financial crisis' impact on the employment of banking sector in Malaysia. In the finance, insurance, real estate and business service sector, a number of 6,596 workers were retrenched. Banks were forced into mergers and acquisition as well as downsizing, trim lean, organizational changes and introduction of new technologies. Excess workers were offered a "voluntary separation scheme." These retrenched workers became the urban poor facing high cost of living and no opportunity for jobs as there is no safety net provided.

• Publications of The Korean Astronomical Society
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• v.25 no.3
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• pp.53-58
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• 2010

The origin of the galaxies represents an important focus of current cosmological research, both observational and theoretical. Its resolution involves a comprehensive understanding of star formation and evolution, galaxy dynamics, supermassive black holes, and the cosmology of the very early universe. In this paper, I will review our current understanding of galaxy formation and review some of the challenges that lie ahead. Specific issues that I address include the galaxy luminosity function, feedback by supernovae and by AGN, and downsizing. I argue that current evidence favours two distinct modes of star formation in the early universe, in order to account for the origin of disk and massive spheroidal galaxies. However perhaps the most urgent need is for a robust theory of star formation.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.3
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• pp.204-210
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• 2016

This study analyzed the amount of displacement of window wipers according to pressure by using finite element analysis (FEA) with KS standards for aluminum alloy window wipers manufactured by die-casting method. The product design was changed over four steps considering the die-casting process to achieve strength greater than that of the conventional steel window wiper. According to the FEA results, the strength of final aluminum alloy window wiper improved by 55% over that of a steel window wiper, and the weight of the former was less by approximately 45%. Therefore, there is the possibility of module downsizing for driving motor capacity. Further, the cost competitiveness improved, and the manufacturing process of aluminum alloy window wipers was simplified.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.679-682
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• 2008

The particle which has two different characteristics on both sides is called Janus particle which is emerging as a key material in microscale transport systems. For example, if one hemisphere has polarity and the other does not, then nonpolar sides would attract each other so that a complex cluster is formed. Thus, this fascinating material can be used as an element of twisting ball panel display, complex micro-scale clusters, drug delivery unit, and active detecting beads. The keywords in developing Janus particle are size and uniformity. Former researches solved uniformity but downsizing still remains a problem. There are three methods to generate small size particles in microchannels: co-flowing, cross-flowing, and elongational flows. In this research, we generate Janus particles smaller than 10-${\mu}$m in diameter using elongational flow in microchannels. And we use UV initiator with Hydrogen UV source to solidify micro size particles. One hemisphere of the particle is coated with rhodamin for visualization.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.261-265
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• 2003

As motor performance enhancement by improving electric design has reached its limit and downsizing issue has risen, the importance of thermal design is increasing. In this study, the flow and temperature distribution were reviewed with the help of CFD analysis and this result was compared with the experimental results. Furthermore, parametric analysis with thermal design structure showed that axial duct width but fan capacity is a critical factor to lower the hot spot temperature in electric motor.

• Journal of the Korean Society of Combustion
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• v.15 no.2
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• pp.27-33
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• 2010

Recently, much attention has been paid to utilizing highly preheated air up to $1,000^{\circ}C$ through waste gas in industrial furnaces. The regenerative burner technology has shown to provide significant reduction in energy consumption (up to 60%), downsizing of the equipment (about 30%) and lower emissions (about 30%) while maintaining high thermal performance of the system since 2000. The object of this study is to develop the flameless regenerative burner for industrial furnaces based on the FLOX(Flameless Oxidation) principle and it has been designed and manufactured as pilot scale. Performance tests are experimentally done and their results are discussed. They showed 1) a very good uniformity in temperature distribution, 2) about 100 ppm in NOx at the temperature $1,300^{\circ}C$, 3) about 95% in temperature efficiency. Besides, the regenerative burner has advantage in easy maintenance and high usage rate of regenerator due to the separate and portable type of heat exchanger.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.833-838
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• 2011

Future powertrain technologies will be developed focused on applications of eco-friendly technology for internal combustion engine, electric vehicle and Fuel Cell Electric Vehicle. But it is expected that these cutting edge technologies will not be applied immediately due to lack of infrastructure, technical and economical reasons. Therefore, numerous developments of internal combustion engine will be carried out for the time being. There have been many turbo engine developments undergoing to maximize the engine performance using turbo charger system in accordance with global trend-green technology and downsizing of engine which coincides with HMC's future development strategy. This study reviews the development process and result of plastic intake manifold module which is firstly developed for turbo engine. CAE simulation and experiments were implanted to evaluate design validity.