• Applied Microscopy
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• v.20 no.1
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• pp.51-64
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• 1990

This experiment was performed to study the morphological changes of the goblet cells in the rabbit duodenal mucosa after common bile duct ligation. Healthy adult rabbits weighting about 2kg body weight were divided to normal and bile duct ligated groups. Common bile duct ligation was performed under ether anesthesia. Experimental animals were sacrificed on the 1st, 3rd, 5th, 7th and 14th day after the operation. Mucosal specimens from the upper part of duodenum were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde, followed by 1% osmium tetroxide, embedded in araldite mixture, cut with LKB-V ultratome, stained with uranyl acetate - lead citrate, and observed with JEM 100 CX II electron microscope. Observed results were as follow : 1. In the early stages(1st-5th day) of the experiments, the goblet cells showed apocrine and merocrine secretion. But those of the late stage(7th and 14th day) groups showed exocytotic merocrine secretion. 2. In the late stage of the experiments, there found than increase of newly formed goblet cells that contain electron lucent cytoplasms. 3. In the goblet cells of normal rabbit, mucous granules with higher or lower electron densities are found together in the cytoplasm, and electron lucent mucous granules occasionally fused together. But in the early stage of the common bile duct ligation, goblet cells contained granules of higher electron densities. 4. Considering the above findings, common bile duct ligation probably initiates the hypersecretion of mucous granules of goblet cells in the early stage, and may facilitate the differentiation of goblet cells in the later stage.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.245-245
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• 2004

This study was carried out to evaluate the possibility of production of kittens by a non-surgical intrauterine insemination (NIUI) or intra-vaginal insemination (IVI) with the Norwegian catheter and using a frozen epididymal sperm (FES). Semen was collected epididymal sperm and frozen in Tris-buffered with 50 × 10/sup 6//㎖. The motility and progressive motility of FES was approximately 40.3±5.8% and 35.9±6.5% after thawing. (omitted)

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.25-28
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• 2001

Today enterprises are bringing forward the strong needs for the Global Work Space that is able to realize the collaboration of the virtual enterprise in order to achieve the rapid entrance to market, the quality improvement as well as the cost reduction of their new products. Especially, they are building the efficient Product Management Infrastructure in parallel with the real-time knowledge management for the information generated in the course of a product lifecycle and the Process Innovation making the Concurrent Engineering possible. Building a system in the web environment cannot be the entire effort to realize the Global Work Space within an enterprise that is an essential factor for the reduction of a product development period which in turn contributes to Time to Market. Various work models and processes are found in enterprises and many different application programs are developed and utilized to support these. This study proposes a scheme for the optimized Collaborative Workflow System Architecture that is able to take in and apply various application programs accompanied by the product development work process. Through this, we are to examine various limits and problems existing in the real-time collaborative system between enterprises and to reform these.

• Current Photovoltaic Research
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• v.5 no.1
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• pp.20-24
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• 2017

Recently, three-dimensional (3D) light harvesting structures are highly attracted because of their high light harvesting capacity and charge collection efficiencies. In this study, we have fabricated $Cu_2ZnSn(S_xSe_{1-x})_4$ based 3D thin film solar cells on PR patterned Molybdenum (Mo) substrates using photolithography technique. Specifically, Mo patterns were deposited on PR patterned Mo substrates by sputtering and the thin Cu-Zn-Sn stacked layer was deposited over this Mo patterns by sputtering technique. The stacked Zn-Sn-Cu precursor thin films were sulfo-selenized to form CZTSSe pattern. Finally, CZTSSe absorbers were coated with thin CdS layer using chemical bath deposition and ZnO window layer was deposited over CZTSSe/CdS using DC sputtering technique. Fabricated 3-D solar cells were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF) analysis, Field-emission scanning electron microscopy (FE-SEM) to study their structural, compositional and morphological properties, respectively. The 3% efficiency is achieved for this kind of solar cell. Further efforts will be carried out to improve the performance of solar cell through various optimizations.

• Journal of Navigation and Port Research
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• v.41 no.1
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• pp.1-8
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• 2017

The estimation of non-linear ship motion is one of the most important issues in recent studies of ship stability. In this paper, bispectral analysis and bicoherence analysis were introduced in order to analyze the non-linear ship motion. In addition to the previously observed non-linear pitching motion in following seas, this study observed the non-linear phase coupling of pitching motion in following & quartering seas, and starboard beam seas. By comparing phase coupling between each frequency quantitatively via the bicoherence analysis, it was confirmed that non-linear phase coupling was much stronger in frequency regions other than the peak frequencies of a power spectrum. Furthermore, it was found out that the results of bicoherence calculation were analagous to each other, although the different normalization methods were applied.

• Proceedings of the KIEE Conference
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• 2004.07e
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• pp.3-9
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• 2004

This research is that concern in mathematics education of Technical high school Department of Electricity in the 7th educational curriculum. Indicated problem of mathematics education of Technical high school Department of Electricity at 7th educational curriculum as that compare mathematics subject contents with difference of Technical high school mathematics education in the 6th and the 7th educational curriculum. And examine major subject contents, analyzed contents of mathematics that must supplement and mathematics which use in major subject. Established contents of electricity mathematics education that need to major learning to satisfy target of technical high school technical education that is presented in the 7th training courses with this analysis

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.10-18
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• 2003

A point of doing this research is to give basic data for junior college having matriculation resources in department of electricity majority to the graduate students from Technical high school in department of electricity. We have examined the effect of the 6th and the 7th educational curriculum and courses in department of electricity on technical high school, and analyzed basic subjects of technical high school and detailed major basis subject of junior college in department of electricity by Educational courses and mathematics education contents. Also we have examined tried to secure advantage of major studying on the basis of result of analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.8
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• pp.855-861
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• 2011

We predict the rolled-strip profile for a 6-high mill using thin rolling theory and a numerical model. In the numerical model, we calculate the distributions of the contact pressures between the rolls and the rolling pressure between the strip and the work roll in the transverse direction using the geometric structure of the 6-high mill and the boundary conditions. We determine the distribution of the rolling pressure in the rolling direction via a thin-foil rolling model using Fleck's theory. We calculate the three-dimensional elastic deformation of the work roll using the pressures of the width and rolling directions. We then obtain the three-dimensional strip profile via the elastic deformation of the work roll during the rolling process. The profile is verified by a thin cold-rolling test and FE simulation.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.4 s.193
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• pp.115-122
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• 2007

Recently, remarkable progress has been made in both technology and production of optical elements including aspheric lens. Especially, requirements for machining glass materials have been increasing in terms of limitation on using environment, flexibility of material selection and surface accuracy. In the past, precision optical glass lenses were produced through multiple processes such as grinding and polishing, but mass production of aspheric lenses requiring high accuracy and having complex profile was rather difficult. In such a background, the high-precision optical GMP process was developed with an eye to mass production of precision optical glass parts by molding press. This GMP process can produce with precision and good repeatability special form lenses such as camera, video camera, aspheric lens for laser pickup, $f-\theta$ lens for laser printer and prism, and me glass parts including diffraction grating and V-grooved base. GMP process consist a succession of heating, forming, and cooling stage. In this study, as a fundamental study to develop molds for GMP used in fabrication of glass lens, we conducted a glass lens forming simulation. In prior to, to determine flow characteristics and coefficient of friction, a compression test and a compression farming simulation for PBK40, which is a material of glass lens, were conducted. Finally, using flow stress functions and coefficient of friction, a glass lens forming simulation was conducted.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1218-1223
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• 2009

Total phenolics and antioxidant activities of water and 80% methanol extract of chestnut inner skin were investigated. The antioxidant properties of both extracts of chestnut inner skin were evaluated using different antioxidant tests, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activities, reducing power, ferric reducing ability of plasma (FRAP), and inhibitory effects on ${\beta}$-carotene bleaching. The 80% methanol extract of inner skin exhibited the higher DPPH, ABTS radical scavenging activities, reducing power, and FRAP than water extract of inner skin and did also in a concentration-dependent manner. However, inhibitory effects on ${\beta}$-carotene bleaching of 80% methanol extract was similar to those of water extract, 35.09 and 39.07% at 1 mg/mL, respectively. The total phenolic contents of water and 80% methanol extract from chestnut inner skin were 5,801.42 and 9,735.56 mg/100 g, respectively. High performance liquid chromatography (HPLC) analysis showed that gallic acid was the predominant phenolic compound in water and 80% methanol extract from inner skin. These water and 80% methanol extracts of chestnut inner skin can be utilized as an effective and safe source of antioxidants.