• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.799-802
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• 1998

As we know, gigabit ethernet is a new technology to be substituted for current fast ethernet used widely in local area network. The switch used in gigabit ethernet should deal with frames in giga-bps. To do such a fast switching, we need that serveral processes meet the budgets, such as MAC address table lookup, several giga speed path setup, fast scheduling, and etc. Especially MAC address table lookup has to be processed in the same speed with speed of incoming packets, thus the bottleneck in the process can cause packet loss by the overflow in the input buffer. We devise new practical hardware hashing method to perform fast table lookup by minimizing the number of external memory access and accelerating with hardware.

• Proceedings of the Korea Database Society Conference
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• 1999.06a
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• pp.403-413
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• 1999

Today's businesses are experiencing intensive global competition and the most accelerating pace of change ever. Competitors have sprung up that were not even on the business's radar. This environment impacts all decisions and strategies as business try to dominate their market or their industry merely to survive. So recently most of organizations are considering on building the data warehouse system to pursuit the business intelligence. We need the proper model to guide the approach to plan building data warehouse system when we want to plan it in considering the organizational status. Therefore we suggest a model to decide the approach to build data warehouse considering the project's environmental factors. First we review Ronald S. Swift(1998)'s five environmental factors that we have to consider when planing to build data warehouse. Then we propose a model to decide DW approach by the degree of those factors to be measured. DW approaches in this model are classified in conservative approach, technological approach, increasing approach. enterprise- wide approach, and ideal approach.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.15-218
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• 1999

Concrete is the most generous, universal main structural material. There is active study for processing quality, stable quality mangement. Especially, strength is basic factor of evaluating stability of concrete building. Regaining required strength and homogeneity is very important to get self-stability in building to evaluate another characteristic. Concrete strength is important to the quality management. But, result of hardened concrete's quality test is hardly reflected to works immediately. When required strength is not enough, it could bring out safe problem, economic and administrative cost. It is pointed out that problems from strength evaluation, so early evaluation of concrete quality is required. From the trend that accelerating high quality concrete development, improving the method of quality test and early evaluation measure is urgent project. Throughout this report, it is suggested the method with use of microwave to evaluate 28-days concrete strength.

• Child Health Nursing Research
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• v.11 no.2
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• pp.240-245
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• 2005

The problem of childhood obesity is accelerating throughout the world. Korea is no longer an exception to this problem. The following topics are discussed in this review article: 1) the linkage between childhood obesity and adult obesity, which is often associated with metabolic diseases such as type2 diabetes, hypertension, cardiovascular diseases, and certain cancers; 2) characteristics of childhood obesity; 3) measurement of obesity and its unique problem; 4) recent trends in interventions for childhood obesity. Lastly, the author points out that nurses are best suited for carrying out interventions to prevent obesity in childhood. As childhood obesity is a risk factor for persistence of obesity into adulthood, the need to consider the priority of prevention of obesity during childhood is emphasized in this review.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.997-1002
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• 2001

There are two types of chloride in concrete; one is added as concrete materials' chloride when concrete's mixing, and .the other is penetrated from the air and sea water in the sea-shore area. These chlorides penetrate into concrete, and they are accumulated inside the concrete with aging. This study aimed to evaluate the chloride ion penetration resistance of concrete containing GGBFS in the sea-shore area. Therefore, the specimens made with the replacement ratios(0, 0.30, 0.45, 0.60) of GGBFS were put into 3% NaCl solution according to the chloride accelerating test of JCI-SC3, and then investigated the weight changes, compressive strength, chloride ion with the depths of the specimens by aging. The result is that the diffusion coefficient of chloride ion is decreased with the increase of replacement ratios when compared to OPC

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.43-48
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• 2001

The use of fly ash in cement and concrete industries has many benefits including engineering, economic, and ecological aspects. However, it has a disadvantage of low strength development, especially at early ages. In this study, in order to overcome this problem, the early strength accelerating agent($NA_{2}$ $SO_{4}$) was selected and applied to the production of high strength concrete(HSC) containing fly ash. It was found that the compressive strength of fly ash concrete incorporating TEX>$NA_{2}$ $SO_{4}$ has greater than that of concrete containing fly ash only until 7 days after casting. From the microstructural point of view, ettringite increased and pores decreased in fly ash concrete incorporating TEX>$NA_{2}$ $SO_{4}$ , leading to the development of early age strength. It was also found that the velocity vs. strength relationship of HSC is considerably different from that of low-strength concrete(LSC). Therefore, in order to predict early age strength of HSC, a estimation equation different from that for LSC is needed.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09b
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• pp.141-144
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• 2003

A composite adaptive dual fuzzy controller combining the approximate mathematical model, linguistic model description, linguistic control rules and identification modeling error into a single adaptive fuzzy controller is developed for a nonlinear system. It ensures the system output tracks the desired reference value and excites the plant sufficiently for accelerating the parameter estimation process so that the control performances are greatly improved. Using the Lyapunov synthesis approach, proposed controller is analyzed and simulation results verify the effectiveness of the proposed control algorithm.

• Aerospace Engineering and Technology
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• v.9 no.2
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• pp.1-7
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• 2010

Fatigue properties of composite materials are extremely important to design durable and reliable helicopter rotor blades. However, it is very difficult to apply conventional fatigue test loads in short period. Therefore, accelerating test speed and facilitating spectrum load realization are required. In this study, we have developed a fatigue testing method that uses a resonance of simply supported beam type blade specimen. This test consists in exciting the blade specimen with a frequency that corresponds to its natural frequency. In that case, the test specimen similar to a beam fixed between two pivot points starts vibrating and is significantly deformed. Resonant fatigue tests were performed by changing exciting vertical amplitude and frequency, and S-N curves of each composite materials were successfully obtained.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.94.1-94.1
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• 2013

Whistler mode chorus waves, which are observed outside the plasmasphere of the Earth's magnetosphere, play a major role in accelerating and scattering energetic electrons in the radiation belts. In this study we developed a predicting scheme of the global distribution of chorus by using the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellite data. First, we determined global spatial distributions of chorus activity, and identified fit functions that best represent chorus intensities in specific L-MLT zones. Second, we determined the specific dependence of average chorus intensity on preceding solar wind conditions (e.g., solar wind speed, IMF Bz, energy coupling degree) as well as preceding geomagnetic states (as represented by AE, for example). Finally, we combined these two results to develop the predicting functions for the global distribution and intensity of chorus. Implementing these results in the radiation belt models should improve the local acceleration effect by chorus waves.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.733-735
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• 2003

Ornithine decarboxylase (ODC) is a key enzyme on the regulation of cellular polyamines. ODC antizyme is a protein that represses ODC through accelerating enzymatic degradation by the 26S proteasome. We have isolated two distinct antizyme cDNA clones (AZS and AZL) from a brain cDNA library constructed with flounder (Paralichthys olivaceus). AZS and AZL cDNA clones were encoding 221 and 218 residues long respectively and revealed 57.7% amino acids sequence identity. The presence of two antizymes mRNA were detected in brain, kidney, liver, and embryo.