• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.2
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• pp.33-41
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• 2005

ZnO epilayer was synthesized by the pulsed laser deposition(PLD) process on Al$_2$O$_3$ subsorte after irradiating the surface of ZnO sintered pellet by ArF(193nm) excimer laser. The epilayers of ZnO were achieved on sapphire(A1203) substrate at the 境mperature of 400$^{circ}$C. The crystalline structure of epilayer was investigated by the Photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of ZnO epilayer measure with Hall effect by van der Pauw mothod are $8.27\times$1016cm$^{-3}$ and 299 cm$^{2}$/V$\cdot$s at 293 K respectively, The temperature dependence of the energy band gap of the ZnO obtained from the absorption spectra was well described by the Varshni's relation, E$_g$(T)= 3.3973 eV - ($2.69\times$ 10$^{-4}$ eV/K)T$^{2}$/(T + 463K). After the as-grown ZnO epilayer was annealed in Zn atmospheres, oxygen and vaccum the origin of point defects of ZnO atmospheres has been investigated by the photoluminescence(PL) at 10K. The native defects of V$_{Zn}$, V$_{O}$, Zn$_{int}$, and O$_{int}$ obtained by PL measurements were classified as a donor or acceptor type. In addition we concluded that the heat-treatment in the oxygen atmosphere converted ZnO thin films to an optical p-type. Also, we confirmed that vacuum in ZnO/Al$_2$O$_3$ did not firm the native defects because vacuum in ZnO thin films existed in the form of stable bonds.

• Applied Microscopy
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• v.21 no.2
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• pp.1-13
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• 1991

In order to investigate the factors of the control mechanism of somitogenesis, early chick embryos (H-H stage $8{\sim}13$) were treated with heat shock, ${\alpha}$-amanitin and cycloheximide and morphological changes of somite were examined by light microscopy, transmission and scanning electron microscopy. In normal chick embryo, somites were formed from the somitomere which preexisted in segmental plate. Somites were wrapped with extracellular collagen fibrils and connected with neural tube, notochord and ectoderm. And then, somites were differentiated to sclerotome, dermatome and myotome by the interaction of nervous tissue. Abnormal somites were observed after formation of six or seven so mites in heat shock treated group. Amounts of collagen fibrils were obviously decreased in this group. In cycloheximide treated group, most so mites were smaller and neural tube formation was incomplete. Chromatins were condenced and formed several heterochromatins in the nucleus of somite cells. Lipid like cytoplasmic dense mass and lipid droplets were also observed. Segmentation of somites seemed to be normal progress in ${\alpha}$-amanitin treated group. Center of somite, however, hollowed in longitudinal sectioned samples. These results suggested that so mites were already existed in the segmental plate as the form of somitomere. Segmented somites were contacted with neural tube or notochord and the somites were tightly connected with each other by the extracellular collagen fibrils which were secreted from neuroepithelium and somite cells. Somites are thought to differentiate into sclerotome, dermatome and myotome by these interactions.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.926-933
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• 2010

Runoff from a parking lot can be highly contaminated nonpoint source due to the impermeability of rainwater. This study presented runoff characteristics of heavy metals especially Zn and Pb from a parking lot during total 17 rain events. Monitoring results showed the first flush phenomenon within 30 min was observed in all rain events, but the event mean concentration (EMC) did not clearly show the characteristics of runoff. The ranges of Pb and Zn was $4{\sim}201{\mu}g/L$ and $131{\sim}672{\mu}g/L$, respectively, and the runoff mass of Zn and Pb was highly to related with the flow rate, and runoff coefficient of rain. The runoff mass of Zn was greater than that of Pb in all events. The runoff mass of Pb was highly correlated with the amount of TSS, and TSS and DOC were was related with the mass of Zn. This result implies that Pb and Zn are mainly existed in the particulate form. The results can be used to as meaningful data in the management of nonpoint source, and in the management in the runoff catchment in the parking lot.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.5
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• pp.406-413
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• 2004

Progress in medical science and cell biology has resulted in the transplantation of human cells and tissues from on human into another, facilitating reproduction and the restoration of form and function, as well as enhancing the quality of life. For more than 40 years, society has recognized the medical and humanitarian value of donation and transplanting organs and tissues. The standard operating procedures of hard tissues reflect the collective expertise and conscientious efforts of tissue bank professionals to provide a foundation for the guidance of tissue banking activities. Procurement of allograft tissues from surgical bone donors is a part of tissue banking. During the past decades the use of bone allografts has become widely accepted for the filling of skelectal defects in a variety of surgical procedures. In particular in the field of orthopaedic and oral and maxillofacial surgery the demand for allografts obtained from either living or post-mortem donors has increased. Hospital-based tissue banks mainly retrieve allografts from living donors undergoing primary total hip replacement for osteoarthritis or hemi arthroplasty for hip fractures and orthgnatic surgery such as angle reduction. Although bone banks have existed for many years, the elements of organized and maintaining a hospital bone bank have not been well documented. The experience with a tissue bank at Korea Tissue Bank(KTB) between 2001 and 2004 provides a model of procurement, storage, processing, sterilization and documentation associated with such a facility. The following report describes the standard operating procedures of hard tissues such as femoral head obtained from living donors.

• Korean Institute of Interior Design Journal
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• v.19 no.6
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• pp.141-149
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• 2010

This thesis is designed to take a close look into the characteristics of architectural space through the standard of beauty, which has been created apart from our desires at certain cultural or historical periods of time. It will try to construct the outline of conception about the beauty throughout many centuries. First of all, contents of the research will focus on the aspects, which people have been considering as beauty eversince the ancient time without having any assumptions on its concept. For example, if the beauty of art has been accepted by the theories of modern aesthetics while degrading the beauty of nature, its value could have possibly been much more appreciated. The standard of beauty has been going through the process of change in such history of mankind. The general standard of beauty, which was established in the ancient time was the proportion and harmony between many elements. Afterwards, beauty was expressed as colors and light in medieval times. Expression of beauty using ugly features such as monsters or demons also existed at the time. Beauty has been periodically developing from supernatural to gracious, rational, noble, romantic, religious, mechanical, and today's media. The concept of beauty established from the above has been appearing throughout various culture such as dress and decoration at the given period of time. It would later affect the formation of space as well as decoration for architectures and styles. It will be analyzed throughout the five design elements; style, composition, materials, components, and form. The thesis would like to find the spatial order of beauty from the result of the analysis. The analysis will examine the possibility for which the recomposition of beauty will be provided as a design process for the new era. The Greek beauty represents a shape. The shape represents proportion and the proportion represents given numbers. However, beauty is being expressed by the opposite process at the present time. In other words, computers will arrange the numbers, which would formalize the proportion between the numbers. Beauty would be presented when the shape is presented as certain forms.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.212-217
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• 2004

The gene coding for mannanase from Bacillus subtilis WL-7, a number of glycosyl hydrolase family 26, was hyperexpressed in Escherichia coli. Two recombinant plasmids, pE7MAN and pENS7, were constructed by introducing the complete mannanase gene and the mature mannanase gene lacking N-terminal signal peptide region into a expression vector pET24a(＋), respectively. The level of mannanase produced by E. coli BL21 (DE3) carrying pENS7, which included the mature mannanase gene, was considerably higher than that by E. coli BL21 (DE3)/pE7MAN. Almost mannanase produced by the recombinant E. coli carrying pENS7 at growth temperature of $37^{\circ}C$ existed as inactive enzyme of insoluble form. Growth at temperature below $31^{\circ}C$ increased the soluble fraction of mannanase having catalytic activity in the recombinant E. coli cells. The highest productivity of active mannanase was observed in cell-free extract of the recombinant E. coli grown at growth temperature ranging from $25^{\circ}C$ to $28^{\circ}C$, while mannanase activity per soluble protein of the cell-free extract was highest in the cells grown at $^31{\circ}C$.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.1
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• pp.107-113
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• 2012

Pollutants in aquaculture system effluent mostly originated from solid wastes including uneaten feed and excreta of cultured species. In this research, DAF(Dissolved Air Flotation) unit is suggested as an integrated solid control unit especially as a form of IIBG(Inline Injection Bubble Generation) process in aquaculture system. Solid removal performance of DAF unit was examined under various operation and salinity conditions with turbidity and suspended solid. Solid waste removal efficiencies were found to be affected by operation conditions including saturator pressure, recycle ratio, coagulant concentration. Solid removal efficiency was higher under higher saturator pressure and recycle ratio under which condition larger number of bubbles is generated. Coagulant is thought to have important role in creating bubble-particle aggregate by showing better removal efficiency with higher concentration. However higher saline water showed less effectiveness in removing solids by DAF(IIBG). Application of DAF(IIBG) process also showed additional effect in phosphate removal and DO(Dissolved Oxygen) supply. Phosphate existed in polluted water was removed up to 46% after treatment, which is thought to attribute to aluminium phosphate precipitation. And DO concentration was found to increase over 50% of initial saturation concentration after the injection of micro-bubbles. Through experiments on solid removal from aquaculture effluent, DAF(IIBG) process is estimated to be effective solid control method. This property can help aquaculture system being installed and operated simply and effectively.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.201-205
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• 1982

As a series of study on the removal of astringency and production of tannin substances, this experiment was conducted to investigate changes of tannin contents and microscopic observation on leaves of persimmon(Diospyros kaki L.). Changes of tannin contents of leaves and fruits in Daegu Bansi(astringent variety) were of similar tendency in content of total and soluble tannin during growth. It seemed therefore that tannin contents of leaves in astringent variety were closely concerned with tannin of fruits. But Fuyu(sweet variety) was different from each other during its growth. Histological form of leaves in microscopic observation had similar tendency between astringent and sweet varieties. It was observed that tannin substances were contained in epidermis cells of levels, that tannin substances were transfered in phloems of nerves system, and that tannin cell existed too in the vicinity of nerves system.

• Korean Journal of Environment and Ecology
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• v.12 no.2
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• pp.156-162
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• 1998

The disposition of ecotourism was surveyed form October 5 to 22 in 1996. 600 persons were participated from 5 big cities including Seoul in Korea. Of those individuals, 48% were males, 52% were females, 50％ of respondents reported that they had gone as far as college, and 38% were 20 years of age. Most percentage of respondents (72%) were not satisfied from their leisure behavior in their daily life, 60% of respondents had a chance to visit outdoor recreation areas per month. The most respondents(75%) didn't hear the concept of ecotourism, but they recognized necessity of the ecotourism development. There was a tendency in the sample for high disposition of ecotourism subjects to be more likely to intend to interest in environmental problems, and participate to environment movement. They were very interested in ecotourism. The differences existed in ecotourists' dispositions of ecotourism, according to their scio-economic characteristics. The potentional ecotourists' intentions of visiting eco-park had strong relationships with the disposition of ecotourism.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.1
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• pp.45-53
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• 2008

Different method of textile fabrication had existed since the ancient times, but the most dominant form was the 'weaving' method which embodies the cross fabrication of vertical and horizontal threads using special weaving machines (looms). In addition, fabrication methods like knitting, felt, and lace were commonly practiced while intertwinement methods like twisting, braiding, and knotting techniques were frequently used for weaving strings and braid type textiles. In the past, people did not pay attention to strings and braids because they were classified as non-textiles, but, in this paper, we have expanded the scope of definition of textile to include strings and braids, and seek to conduct in-depth research on various different intertwinement of textiles. The adaptation of intertwinement method in arts and crafts enables limitless creative works reflecting the ever-changing taste and style of the creator. This creativity is further broadened by the fact that intertwinement methods encompass no set patterns and the subject and shape of its creation is as broad as its artistic pursuits. We can infer the knowledge of our ancestors, their aesthetic taste, and the pattern of life from these creations. In addition, these creations can provide comfort and improve the quality of life of modem people who are deeply deprived of sentimental and emotional solitude in the technological civilization of the 21stcentury. The main purpose of this paper is to examine traditional Korean arts and crafts made using the intertwinement methodology through the context of strings, braids, straw crafts and knotting method. Then it will conduct through research on the different materials, forms, characteristics, usage and other key notions based on the currently preserved records and relics to contribute to the research on traditional textiles and provide the foundations to the development of the Korean culture and cultural products, reflecting the true sole and aesthetics of traditional Korean textile crafts.