• Journal of Biosystems Engineering
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• v.37 no.2
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• pp.113-121
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• 2012

Purpose: Particle separation in solution is one of important process in a unit operation as well as in an extract preparation for biosensors. Contrary to centrifuge-type of mesh-type filter, using an ultrasonic standing wave make the filtering process continuous and free from maintenance. It is needed to investigate the characteristics of particle movement in the ultrasonic standing wave field. Methods: Through the computer simulation the effects of major design and driving parameters on the alignment characteristics of particles were investigated, and a cylindrical chamber with up-stream flow type was devised using two circular-shape PZTs on both sides of the chamber, one for transmitting ultrasonic wave and the other for just reflecting it. Then, the system performance was experimentally investigated as well. Results: The speed of a particle to reach pressure-node plane increased as the acoustic pressure and size of particle increased. The maximum allowable up-stream flow rate could be calculated as well. As expected, exact numbers of pressure-node planes were well formed at specific locations according to the wavelength of ultrasonic wave. As the driving frequency of PZT got close to its resonance frequency, the bands of particles were observed clearer, which meant the particles were trapped into narrower space. Higher excitation voltages to the PZT produced a greater acoustic force with which to trap particles in the pressure-node planes, so that the particles gathered could move upwards without disturbing their alignments even at a higher inlet flow rate. Conclusions: This research showed the feasibility of particle separation in solution in the continuous way by an ultrasonic standing wave. Further study is needed to develop a device to collect or harvest those separated particles.

• Korean Institute of Interior Design Journal
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• v.15 no.5 s.58
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• pp.60-67
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• 2006

An architecture is a result from representation of design knowledge by architect's creative thinking, and operated only in his internal organization system. Design knowledge based upon the experience that they have achieved in the past as well as the informations they have accumulated over the time. In this point of view, the Schema that formed by problems settlement and process repetitions for the best conclusion, not only play an important part in the designer's thinking system about a specific problem but also appeared by distinctive features. This research looks to achieve a new design method by finding out how architects express traditionality in the contemporary house through schema. This research analyze contemporary house built in seoul of 1990's. The result are as followings. First, Schema is a 'frame' that already exist in the architect's thinking, will make a good guide about express the traditionality. Second, We found out several distinctive characters in the form and the space. The form is divided in five types. It is an condensed form of roof image, the metamorphosis of form grammar, the change of part details, the representation of design principle and the directly expression. Lastly, In the space, it is the borrow of the connection method of inside and external space, the three parts composition of the space, the adaptation of 'Madang' and the Independent composition of the space due to 'Chae'

• Journal of Korean Medical classics
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• v.20 no.2
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• pp.201-230
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• 2007

Basic summary of the medical administration : First of all Ming dynasty was at its last stage of dynastic era that the politics reached absolute autocracy. The influence of centralized power lead to systematical medical administration management system that was generally formed around Tai Yi Yuan(太醫院). Criticizing treatments via shamanism with supernatural powers and advent of strengthening medical concepts were steps toward a new phase. Medical education in regional areas showed drastic development and preventative medicine on epidemics as well as relief work succeeded to a certain amount. Overall Ming(明) dynasty has somewhat of a growth in some areas keeping the basics of Tang(唐) Song(宋) and Yuan(元)'s medical administration, however basically, unique contribution was not shown much. But on the other hand, measures such as common medical system, reserving incompetent doctors, positioning medical officers by the amount of contributions, paying salary with medicine instead of currency brought losses on medical development.

• Journal of Korean Society for Geospatial Information Science
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• v.2 no.2 s.4
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• pp.43-53
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• 1994

GSIS(geo-spatial information system), particularly when utilized in hazard management decision, is one of hazard analysis tool. Data of GSIS input from digitizing or scanning of map or aerial photos. This paper focuses upon the hazard prediction in GSIS and RS analysis to assess map, aerialphotos, satellite imagery and soil map. This study found computation of hazard area analysis. the results is formed as raster data model of quadtree. Authors knew more accurate results of overlay. This paper shows building up integrated data base as well as search of hazard area in aerial photographs.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.85.1-85.1
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• 2014

The progenitors of Type Ibc supernovae (SNe Ibc) have been believed to be massive Wolf-Rayet (WR) stars, formed either through stellar wind mass loss or Roche-lobe outflow in a binary system. But observations indicate that ordinary SNe Ibc have relatively low ejecta masses (~2 Msun), which is not compatible with the WR star scenario for SN Ibc progenitors. On the other hand, helium stars in binary systems which can be produced via mass transfer are also suggested as a possible candidate for SN Ibc progenitors. Binary star evolution models predict that SN Ibc progenitors having final masses of 3-7 Msun can be produced, but their observational properties are not well understood. In this study, we present the parameter study on the observational constraints of helium stars of 3-5 Msun in binary systems using evolutionary models and the atmospheric radiative transfer code CMFGEN. We present the predicted magnitudes and spectra of helium stars in optical bands for different wind velocity profiles and mass loss rates. We also present those observables of the progenitor binary system considering O-type companion stars. Based on the results, we discuss the expected observational properties of SN Ibc progenitors in binary systems. In particular, we discuss the constraints on the progenitor of the SN Ib iPTF13bvn of which progenitor candidate has been identified for the first time in pre-explosion images among SNe Ibc.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.475-479
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• 2012

Thermal energy storage (TES) systems using Microencapsulated phase change material (MPCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. We examined a way to incorporate MPCMs with building materials through application for wood-based flooring. Wood-based flooring is commonly used for floor finish materials of residential buildings in Korea. However, wood-based flooring has not performed the characteristic of heat storage. This study is aimed at manufacturing high thermal efficiency wood flooring by increasing its heat storage using MPCM. As a result, this study confirmed that MPCM is dispersed well in adhesive through the scanning electron microscopy analysis. From the differential scanning calorimetry analysis, it can be confirmed that this composite has the characteristic of a thermal energy storage material. Also, we analyzed how this composition was formed by physical combination through the Fourier transform infrared analysis. Also, we confirmed the bonding strength of the material by using the universal testing machine.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.12
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• pp.1161-1170
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• 2014

Delta sash is an important part of automobile door, which has the functions of supporting and guiding seesaw of car's window, preventing dust and air from outside. In previous manufacturing process, each part of the delta sash was independently formed by tandem processes, and rubber is bonded to steel by poisonous glue. So, the previous processes, including roll forming process and toxic gases, had low production rate and high failure rate. In this study, progressive process design of the delta sash was proposed in order to increase productivity and high utilization of the materials. And instead of the poisonous glue used for adhesion of rubber in the previous tandem process, embossing and piercing processes were designed in the new guide to help the rubber to adhere well to steel. And the optimal piercing distance was designed to ensure structural safety, and prototypes were manufactured for verifying reliability of the processes.

• Journal of Plant Biotechnology
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• v.30 no.3
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• pp.269-273
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• 2003

In order to develop an efficient micropropagation protocal for Eucalyptus pellita, on in vitro culture system has been was established by inducing axillary buds from greenhouse stock materials. Among 6different media tested, DKW medium was the best ot induce bast induce both shoot proliferation and growth. Average number of proliferated shoots of 403per explant was obtained at the concentration of 0.1mg/LBA. Most of the stem materials excreted phenolic compounds at the proximal part of the explant and caused darking of the media. Therefore, it was necessary to transfer frequently to a fresh medium and/or to add activated charcoal at the concentration of 0.02％(w/v). Generally on vitro roots were formed easily on 1/2DKW medium with NAA treatment. All the explants rooted at the medium containing 0.2mg/L NAA and displayed vigorous root growth in vitro culture conditions. After transferred to an artificial soil mixture (peatmoss: vermiculrite: perlite, 1:1:1, v/v/v) in the greenhouse, most rooted plantlets survived well without any morphological abnormalities. The results show that the species can be micropropagated effectively by the application of axillary bud culture system.

• International Journal of Highway Engineering
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• v.17 no.5
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• pp.1-10
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• 2015

PURPOSES : A finite difference model considering snow melting process on porous asphalt pavement was derived on the basis of heat transfer and mass transfer theories. The derived model can be applied to predict the region where black-ice develops, as well as to predict temperature profile of pavement systems where a de-icing system is installed. In addition, the model can be used to determined the minimum energy required to melt the ice formed on the pavement. METHODS : The snow on the porous asphalt pavement, whose porosity must be considered in thermal analysis, is divided into several layers such as dry snow layer, saturated snow layer, water+pavement surface, pavement surface, and sublayer. The mass balance and heat balance equations are derived to describe conductive, convective, radiative, and latent transfer of heat and mass in each layer. The finite differential method is used to implement the derived equations, boundary conditions, and the testing method to determine the thermal properties are suggested for each layer. RESULTS: The finite differential equations that describe the icing and deicing on pavements are derived, and we have presented them in our work. The framework to develop a temperature-forecasting model is successfully created. CONCLUSIONS : We conclude by successfully creating framework for the finite difference model based on the heat and mass transfer theories. To complete implementation, laboratory tests required to be performed.

• KIEAE Journal
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• v.4 no.2
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• pp.49-56
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• 2004

This study intends to propose the fundamentals of 'Ecovillage' design by researching into the cycle system of material of 'Crystalwaters' which is having been in charge of a leading role of GEN since 1996 (GEN was formed in 1996) as Ecovillage in Australia. First, to secure the water resources, we can store up rain and the water of valley, and dam. Second, we are able to use the natural filter apparatus, do tree-planting of roof to gain better quality of water. Third, it is to save the energy as supplying water. For it, we make the best of a gravity that is one of the cycle principle of water. Forth, to build a Dam can make a site of scenic beauty, do the role of recreation place and provide against emergencies (a fire, drought) as well as make a mild climate. Fifth, it can reduce the environment load because of sewage and garbage as making it compost. This is possible by treating biologically using composting apparatus of the dry or wet process. Sixth, it is to reduce the environmental pollution as to discharge seperating a recycable waste, an organic matter being able to make it compost. Finally, first of all, environmentally friendly inhabitant consciousness from lifestyle and production style plays an importent part for water cycle and the ecological cycle of waste and sewage.