• Journal of Korean Society of Water and Wastewater
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• v.20 no.6
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• pp.837-848
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• 2006

This paper presents the test results of biological aerated filtration(BAF) process to replace activated sludge process by enhancing treated effluent quality and reducing the costs. In BAF process both BOD and SS compounds in wastewater are degraded and removed by biological reaction and filtration. Upflow BAF with expanded polypropylene media and downflow BAF with ceramic media were used to investigate the effects of hydraulic and organic loads on effluent quality. As a result, in BAF processes which has different media, upflow BAF reactor shows 5% higher efficiency than downflow BAF and this phenomena caused by backwashing methods and operational conditions. The results of influence factors analyzed by Factor Analysis Method in BOD and SS treatment efficiency are the size of media, hight of media bed and type of media. The quantitative effects of media size are 5.73% in TBOD, 5.78% in SBOD and 7.65% in TSS, so we confirmed the main factor is media size.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.915-921
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• 2008

In most PEM fuel cell research, effects of cell geometry, physical properties of component such as membrane, carbon cloth, catalyst, etc. and water transport phenomena are key issues. The scope of these research was limited to single cell and stack except BOP(Balance of plant) of fuel cell. The research fouced on the fuel cell system usually neglect to consider detailed transport phenomena in the cell. The research of the fuel cell system was interested in a system performance and system dynamics. In this paper, the effect of the anode recirculation is calculated using the 2D steady-state model. For this work, 2D steady-state modeling and experiments are performed. For convenience of modifying of model equation, not commercial pakage but the in-house algorithm was used in simulation. For an vehicle industry, the analysis of the anode recirculation system helps the optimization of operating condition of the fuel cell.

• Journal of the Korean Mathematical Society
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• v.32 no.4
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• pp.877-888
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• 1995

Many authors have utilized a Pareto distribution because of its wide applicability in socio-economic, physical and biological phenomena.

• Journal of The Korean Association For Science Education
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• v.29 no.3
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• pp.348-358
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• 2009

The purpose of this study was to investigate brain activation pattern and functional connectivity network during experimental design on the biological phenomena. Twenty six right-handed healthy science teachers volunteered to be in the present study. To investigate participants' brain activities during the tasks, 3.0T fMRI system with the block experimental-design was used to measure BOLD signals of their brain and SPM2 software package was applied to analyze the acquired initial image data from the fMRI system. According to the analyzed data, superior, middle and inferior frontal gyrus, superior and inferior parietal lobule, fusiform gyrus, lingual gyrus, and bilateral cerebellum were significantly activated during participants' carrying-out experimental design. The network model was consisting of six nodes (ROIs) and its six connections. These results suggested the notion that the activation and connections of these regions mean that experimental design process couldn't succeed just a memory retrieval process. These results enable the scientific experimental design process to be examined from the cognitive neuroscience perspective, and may be used as a basis for developing a teaching-learning program for scientific experimental design such as brain-based science education curriculum.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.641-644
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• 2005

The study on the interaction forces of some biological materials is important to understanding biological phenomena and their application to practical purpose. This paper introduces a measuring technique for biological adhesive forces using the AFM(Atomic Force Microscope). Since no standardized thesis on adhesive forces exist, the adhesive forces is defined as adhesive forces against a hardened surface of biological materials. To grant the results are meaningful, which is based on the understanding the surface characteristics of biological materials using the AFM, a nominal value of average adhesive force per unit area should be measured. Therefore the modified AFM probe with small micro glass bead was proposed so that it can guarantee the required contact area for measuring the average adhesive forces. A pyrex glass substrate with circular patterns, which was fabricated by micromachining technique, is introduced in order to controll the contact area. The two types of mussel adhesive proteins, Celltak and recombinant-MGFP5, were tested by the proposed measuring method. The test results show that the adhesive force of the mussel adhesive proteins can be reliably measured by use of this method.

• Advances in nano research
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• v.1 no.3
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• pp.133-151
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• 2013

The availability of advanced nanotechnological methodologies (experimental and theoretical) has widened the investigation of biological/organic matter in interaction with substrates. Minerals are good candidates as substrates because they may present a wide variety of physico-chemical properties and surface nanostructures that can be used to actively condense and manipulate the biomolecules. Scanning Probe Microscopy (SPM) is one of the best suited techniques used to investigate at a single molecule level the surface interactions. In addition, the recent availability of high performance computing has increased the possibility to study quantum mechanically the interaction phenomena extending the number of atoms involved in the simulation. In the present paper, firstly we will briefly introduce new SPM technological developments and applications to investigate mineral surfaces and mineral-biomolecule interaction, then we will present results on the specific RNA-mineral interaction and recent basics and applicative achievements in the field of the interactions between other fundamental biological molecules and mineral surfaces from both an experimental and theoretical point of view.

• Korea-Australia Rheology Journal
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• v.14 no.4
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• pp.203-207
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• 2002

Particle-particle interaction is of great importance in the study of suspension rheology. In this research we have investigated the hydrodynamic interaction between two identical cylinders in viscoelastic fluids numerically as a model problem for the study of viscoelastic suspension. We confine two neutrally buoyant cylinders between two parallel plates and impose a shear flow. We determine the migration velocity of two cylinders. The result shows that cylinders move toward or away from each other depending upon the initial distance between them and that there is an equilibrium distance between two cylinders in viscoelastic fluids regardless of the initial distance. In the case of Newtonian fluid, there is no relative movement as expected. The results partly explain the chaining phenomena of spherical particles in shear flows of viscoelastic fluids.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.218-221
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• 2000

By the end of the $21^st$ century, the world population will surely far exceed the current 6.6 billion, threatening the essential requirements for life due to environmental deterioration and shortened food supply. To overcome this looming threat, we must develop new biotechnologies. There are so many known natural phenomena that we may have neglected, not perceiving them as blessings of nature. Many more remain unknown. We must examine each of them carefully since the many tricky and complicated mechanisms behind simple natural workings could provide us with attractive research targets. How then do we apply these complicated natural mechanisms to agricultural/ industrial production?.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.353-357
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• 2003

Although it is more and more well accepted that modeling is a help for experimental biology, little is known about how to integrate physiological processes in general. The fact that no general theory exist in biology has big consequences, the most important being the difficulty to integrate biological phenomena. 1 will present a solution for the three dependent following issues: i) in an appropriate theoretical framework, integration consists in coupling models that each describe physiological mechanisms (formalization is a necessary condition to integration); ii) a biological theory with its own concepts leads to unifying principles in biology that are different from and complementary to physical principles; iii) such a formalized theory consists in a representation in terms of functional interactions and a specific formalism(S-Propagator). Hence a biological theory is of a topological and geometrical nature, in contrast to physical theories that are of a geometrical nature. An application to the interpretation of intelligence is proposed, based on the "intelligence"of movement.

• BMB Reports
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• v.53 no.7
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• pp.357-366
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• 2020

Currently, most biological research relies on conventional experimental techniques that allow only static analyses at certain time points in vitro or ex vivo. However, if one could visualize cellular dynamics in living organisms, that would provide a unique opportunity to study key biological phenomena in vivo. Intravital microscopy (IVM) encompasses diverse optical systems for direct viewing of objects, including biological structures and individual cells in live animals. With the current development of devices and techniques, IVM addresses important questions in various fields of biological and biomedical sciences. In this mini-review, we provide a general introduction to IVM and examples of recent applications in the field of immunology, oncology, and vascular biology. We also introduce an advanced type of IVM, dubbed real-time IVM, equipped with video-rate resonant scanning. Since the realt-ime IVM can render cellular dynamics with high temporal resolution in vivo, it allows visualization and analysis of rapid biological processes.