• Journal of the Optical Society of Korea
• /
• v.18 no.6
• /
• pp.691-697
• /
• 2014

Optical measurements of the morphological and biochemical imaging of phytoplankton are presented. Employing quantitative phase imaging techniques, 3-D refractive index maps and high-resolution 2-D quantitative phase images of individual live phytoplankton are simultaneously obtained without exogenous labeling agents. In addition, biochemical information of individual phytoplankton including volume, mass, and density of individual phytoplankton are also quantitatively obtained from the measured refractive index distributions. We expect the present method to become a powerful tool for the study of phytoplankton.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.579-579
• /
• 2012

Graphene has recently been a subject of much interest as a potential platform for future nanodevices such as flexible thin-film transistors, touch panels, and solar cells. And chemical vapor deposition (CVD) and related surface segregation techniques are a potentially scalable approach to synthesizing graphite films on a variety of metal substrates. The structural properties of such films have been studied by a number of methods, including Raman scattering, x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and transmission electron microscopy (TEM). An understanding of the structural quality and thickness of the graphite films is of paramount importance both in improving growth procedures and understanding the resulting films' electronic properties. In this study, we synthesized the few-layered grapheneunder optimized condition to figure out the growth mechanism seen in CVD-grown graphenee by using various electron microscope. Especially, we observed directly film thickness, quality, nucleation site, and uniformity of grpahene by using AEM. The details will be discussed in my presentation.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.4 no.1
• /
• pp.1-10
• /
• 1994

It is well known that crystal growth is an essential area of research for optoelectronic materials. In the present paper the growth techniques and the advanced progress in development of crystal materials important for optoelectronic applications are described. New growth techniques, developed in the authors' laboratory, enabling the introduction of expanded applications of new materials are presented. After a review of recent developments of new techniques for optoelectronic materials, own experimental studies will be discussed.

• The Journal of the Korean dental association
• /
• v.48 no.2
• /
• pp.96-105
• /
• 2010

Titanium implant is used as the most popular dental material for replacement of missing teeth recently. A lot of studies on the surface modification of titanium implant have been carried out for enhancing osseointegration. The surface modification techniques could be classified as follows; topographic modifications which provide roughness and porosity, chemical surface modificationss or deposition of osseoconductive materials, and biochemical modifications to immobilize bone growth factors on titanium surface. In this study, the current and ongoing surface modification techniques and its typical characteristics used in clinics were reviewed. In the future, study and implication about biochemical modifications including patient' s individual characteristics will be important.

• International Journal of Advanced Culture Technology
• /
• v.5 no.3
• /
• pp.40-45
• /
• 2017

This data mining technique was used to extract useful information from percutaneous coronary intervention data obtained from the US public data homepage. The experiment was performed by extracting data on the area, frequency of operation, and the number of deaths. It led us to finding of meaningful correlations, patterns, and trends using various algorithms, pattern techniques, and statistical techniques. In this paper, information is obtained through efficient decision tree and cluster analysis in predicting the incidence of percutaneous coronary intervention and mortality. In the cluster analysis, EM algorithm was used to evaluate the suitability of the algorithm for each situation based on performance tests and verification of results. In the cluster analysis, the experimental data were classified using the EM algorithm, and we evaluated which models are more effective in comparing functions. Using data mining technique, it was identified which areas had effective treatment techniques and which areas were vulnerable, and we can predict the frequency and mortality of percutaneous coronary intervention for heart disease.

• 한국전산유체공학회:학술대회논문집
• /
• 2011.05a
• /
• pp.68-74
• /
• 2011

Recently, thanks to the advanced computational power and numerical methods, it is made possible to analyze the flow around moving bodies using computational fluid dynamics techniques. In those simulations, moving mesh techniques should be able to represent both the body motion and boundary deformation, which are frequently encountered in fluid-structure interaction and/or six degree-of-freedom problems. In the present study, the staggered loosely coupling algorithm was used for fluid-structure interaction and the Laplacian operator based technique was used for moving mesh. For the verification of the developed computational method, the flow around a two-dimensional cylinder was simulated and analyzed.

• Journal of the military operations research society of Korea
• /
• v.24 no.1
• /
• pp.68-87
• /
• 1998

Techniques from decision analysis and expert system have both been extensively used in the development of computerized decision aids, although each discipline uses different approaches in knowledge (information or input) acquisition, representation, and problem solving methodology. From the perspective of many types of practical decision aiding applications, both normative decision aids and expert system technology have significant limitations. Many research efforts have been exerted toward complementing the one's deficiency with the other's possible techniques or vice versa. In this paper, among many possible complementary techniques for better decision aiding between decision analysis and expert system, we focus on the using prescriptive methodology of decision analysis which incorporates user's preference knowledge for conflict resolution in rule based expert system.

• Proceedings of the KSRS Conference
• /
• 1998.09a
• /
• pp.163-168
• /
• 1998

Extracting a Digital Elevation Model (DEM) from spaceborne imagery is important for cartographic applications of remote sensing data. The procedure for such DEM generation can be divided into stereo matching, sensor modelling and DEM interpolation. Among these, DEM interpolation contributes significantly to the completeness and accuracy of a DEM and, yet, this technique is often considered "trivial". However, na\ulcornere DEM interpolation may result in a less accurate and sometimes meaningless DEM. This paper reports the performance analysis of various DEM interpolation techniques. Using a manually derived DEM as reference, a number of sample points were created randomly. Different interpolation techniques were applied to the sample points to generate DEMs. The performance of interpolation was assessed by the accuracy of such DEMs. The results showed that kriging gave the best results at all times whereas nearest neighborhood interpolation provided a fast solution with moderate accuracy when sample points were large enough.

• Nuclear Engineering and Technology
• /
• v.37 no.2
• /
• pp.127-138
• /
• 2005

Approaches to several recent issues in the operation of nuclear power plants using computational intelligence are discussed. These issues include 1) noise analysis techniques, 2) on-line monitoring and sensor validation, 3) regularization of ill-posed surveillance and diagnostic measurements, 4) transient identification, 5) artificial intelligence-based core monitoring and diagnostic system, 6) continuous efficiency improvement of nuclear power plants, and 7) autonomous anticipatory control and intelligent-agents. Several changes to the focus of Computational Intelligence in Nuclear Engineering have occurred in the past few years. With earlier activities focusing on the development of condition monitoring and diagnostic techniques for current nuclear power plants, recent activities have focused on the implementation of those methods and the development of methods for next generation plants and space reactors. These advanced techniques are expected to become increasingly important as current generation nuclear power plants have their licenses extended to 60 years and next generation reactors are being designed to operate for extended fuel cycles (up to 25 years), with less operator oversight, and especially for nuclear plants operating in severe environments such as space or ice-bound locations.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.4 no.3
• /
• pp.283-287
• /
• 2004

In this paper, a method of designing the efficient batch blind equalization with low complexity using a micro genetic algorithm (GA), is presented. In general, the blind equalization techniques that are focused on the complexity reduction might be carried out with minor effect on the performance. Among the advanced various subjects in the field of GAs, a micro genetic algorithm is employed to identity the unknown channel impulse response in order to reduce the search space effectively. A new cost function with respect to the constant modulus criterion is suggested considering its relation to the Wiener criterion. We provide simulation results to show the superiority of the proposed techniques compared to other existing techniques.