• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.3
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• pp.244-248
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• 2000

It was investigated and analized on the construction and hull form for the ordinary fishing boat of south coast in Korea, and then analogized on the shipbuilding technology of fishing boat and fishing type around 1900 by B-spline form parameter method. The results obtained can be summarize as follows : (1) It was known that the boats used in this study have more narrow hull form than that of ancient fishing boats and their hull form was improved around 1900. (2) Keel was composed of bar keel with angle cross section. The stem corner have a material of bar stem and makes a sharp pointed stem. (3) Shell plate was jointed by the rabbetted clinker joint method. (4) It was investigated that anchovy drag net fishing boat has high L/B, L/D, B/D value as compared with drift gill net fishing boat. (5) Two boats have a good stability and particularly anchovy drag net fishing boat have a better stability value in comparison to the drift gill net fishing boat.

• Journal of Chest Surgery
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• v.21 no.5
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• pp.803-815
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• 1988

The present experiments were performed to confirm the hypothesis that xanthine oxidase[XOD], as a source and mechanism of oxygen radical production, plays an important role in the genesis of the reperfusion injury of ischemic myocardium. The experimental ischemic-reperfusion injury was induced in isolated, Langendorff preparations of rat hearts by 60 min. Of global ischemia with aortic clamping followed by 20 min. of reperfusion with oxygenated Krebs-Henseleit solution[pH 7.4, 37*C]. The results were as follows: 1. The releases of creatine phosphokinase and a lipid peroxidation product, malondialdehyde[MDA] into the coronary effluent were abruptly increased upon reperfusion of ischemic hearts. The increases of the enzyme and MDA were suppressed significantly in the hearts removed from rats pretreated with allopurinol, a specific XOD inhibitor[20mg/kg, oral, 24 hrs and 2 hrs before study]. This effect of allopurinol was comparable to that of oxygen radical scavengers, superoxide dismutase[5, 000U] and catalase[12, 500 U]. 2. The increased SOD-inhibitable reduction of ferricytochrome C, which was infused to the hearts starting with reperfusion, was significantly suppressed in allopurinol pretreated hearts. 3. Activities of myocardial XOD were compared in the normal control hearts and the ischemic ones. Total enzyme activities were not different in both hearts. However, comparing with the control, the ischemic ones showed higher activity in 0-form and lower activities in D-form and D/O-form. 4. In the ischemic hearts, phenylmethylsulfonyl fluoride, a serine protease inhibitor, prevented significantly the increase of 0-form and the decreases of D and D/O-form, while thiol reagents did not affect the changes of the enzyme. 5. The increase of 0-form and the decreases of D and D/0-form were not significant in both calcium-free perfused and pimozide, a calmodulin inhibitor, treated ischemic hearts. 6. The SOD-inhibitable reduction of ferricytochrome C were suppressed by PMSF and pimozide treatment as well as by calcium-free perfusion. It is suggested from these results that in the ischemic rat myocardium, xanthine oxidase is converted to oxygen radical producing 0-form by calcium, calmodulin-dependent proteolysis and plays a contributing role in the genesis of ischemic-reperfusion injury by producing oxygen free radicals.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.74-86
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• 2020

This study discussesresearch and development of large-sized 3D printers that can be applied to construction and civil engineering for various designs of protective casing on foam liner for concrete exteriors. The consistent use of concrete represents the current surroundings. However, concrete exteriors in Korea have not considered the regional characteristics, but the concrete has been poured solely for economical aspects for the last decade or two. There are many cases of poor installation and not enough design development projects to correct it. This study was conducted to apply various patterns, regional characteristics, and 3D printing for protective casing design for foam liner to create various designs for the concrete walls. Therefore, we started researching on a large 3D printer, and designed and developed this system. Considering the chronological process, the properties of concrete structures were identified, the application of designs for concrete in Korea and abroad and the 3D printing materials for the protective casing were surveyed and analyzed, and a stereotype was produced in the first year to study designs for the beauty of concrete surfaces. In the second year, images of regional characteristics were gathered, design ideas for regional promotion were derived, virtual images were produced along with design modeling to simulate the appearances, and verify the effect of application and promotion. Finally, in the third year, the 3D printer for concrete foam liner was constantly improved to analyze the 3D printing program and the various library elements to complete an actual large-sized 3D printer.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.8
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• pp.52-59
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• 2021

In this study, we experimentally evaluated the mechanical properties and geometric form accuracy in FDM 3D printing processes based on the printing direction, building direction, and layer thickness. The specimen test results showed that the tensile strength increased by over 33% in the printing direction compared to the direction perpendicular to printing and the tensile strength becomes larger as the layer thickness decreased. Furthermore, the tensile and impact strengths in the building direction were significantly reduced due to the difference in the interlayer joining and bonding strengths of the fused material. Additionally, shrinkage of the material due to phase change induced curl distortion especially in thin and long 3D-printed products, which increased as the layer thickness increased.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1608-1615
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• 2016

This study was conducted to determine the solubility of copper (Cu) in two sources of copper(II) sulfate ($CuSO_4$) including monohydrate and pentahydrate and three sources of dicopper chloride trihydroxide (dCCTH) including ${\alpha}$-form (dCCTH-${\alpha}$), ${\beta}$-form (dCCTH-${\beta}$), and a mixture of ${\alpha}$- and ${\beta}$-form (dCCTH-${\alpha}{\beta}$) at different pH and a 3-step in vitro digestion assay for pigs. In Exp. 1, Cu sources were incubated in water-based buffers at pH 2.0, 3.0, 4.8, and 6.8 for 4 h using a shaking incubator at $39^{\circ}C$. The $CuSO_4$ sources were completely dissolved within 15 min except at pH 6.8. The solubility of Cu in dCCTH-${\alpha}$ was greater (p<0.05) than dCCTH-${\beta}$ but was not different from dCCTH-${\alpha}{\beta}$ during 3-h incubation at pH 2.0 and during 2-h incubation at pH 3.0. At pH 4.8, there were no significant differences in solubility of Cu in dCCTH sources. Copper in dCCTH sources were non-soluble at pH 6.8. In Exp. 2, the solubility of Cu was determined during the 3-step in vitro digestion assay for pigs. All sources of Cu were completely dissolved in step 1 which simulated digestion in the stomach. In Exp. 3, the solubility of Cu in experimental diets including a control diet and diets containing 250 mg/kg of additional Cu from five Cu sources was determined during the in vitro digestion assay. The solubility of Cu in diets containing additional Cu sources were greater (p<0.05) than the control diet in step 1. In conclusion, the solubility of Cu was influenced by pH of digesta but was not different among sources based on the in vitro digestion assay.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4726-4732
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• 2013

The Domestic boat has been manufactured by hull form of typical foreign boat. In this study, design environment for polyethylene boat is analysed to create new hull form of the boat and design elements are extracted from existing boats and consumer preferences. Key elements in polyethylene boat design are three words "semi-classic, urban and sporty". Hull resistance and engine power for new developed boat can be expected by Orca 3D program. This result indicates that engine power of the boat is much less than that of commercial boat.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.112-113
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• 2019

In this study, development of 3D software for automated formwork design was conducted to achieve optimization and reduction of labor for temporary work. Through the literature review, the current technical level was identified and the required functions of 3D software for automated formwork design were derived. The 3D software should be developed with the aim of automating 3D design, improving construction quality and utilizing the Internet of Things. As a preliminary step to develop 3D software, the prototype demo version was developed to implement 3D design automation function, which confirm the possibility of 3D software development.

• Korean Institute of Interior Design Journal
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• v.13 no.3
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• pp.187-196
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• 2004

The purpose of this study is to develope'a digital space design process using user's motion data' through a theoretical and experimental study. In the progress of developing a developing of design process, this study was concentrated on searching a digital method applying user's interactive reflections. As introducing a concept of space form being generated by user's experiences, we proposed'a digital design process using user's motion data'. In the experimental stage, user's motion data were extracted and transferred as digital information by user behavior analysis, optical motion capture system, immersive VR system, 3D softwares com computer programming. As the result of this study, another useful digital design process was embodied by building up a digital form-transforming method using 3D softwares providing internal algorithm. This study would be meaningful in terms of attempting a creative and interactive digital space design method, avoiding dehumanization of existing ones through the theoretical study and the experimental approach.

• International Journal of Advanced Culture Technology
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• v.7 no.1
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• pp.243-247
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• 2019

The most commonly used 3D modeling file formats are OBJ (Wavefront file format specification) and STL (STereoLithography). Although they have a common point of view in 3D on the screen, detailed functions are different according to purpose of development. OBJ is the most commonly used 3D file format and STL is mainly used as 3D file format for 3D printing. However, in the field of Scientific Visualization, precise analysis is required. There is a difference in accuracy depending on the type of 3D file format. OBJ and STL are not suitable for delicate surface description because they form meshes in the form of triangular polygons. And if you increase the number of triangle polygons, it will be smoother, but the file size also increases exponentially and causes excessive CPU usage. In contrast, VTK provides a variety of polygon structures, including triangular polygons as well as rectangular polygons and cube polygons. Thus, delicate surface depiction is possible. Delicate surface rendering is possible and file size is not large. This paper describes the concept and structure of VTK. We also compared the load times and file sizes between VTK, STL, and OBJ in the Chrome browser. In addition, the difference in surface rendering ability between VTK, STL, and OBJ is intuitively viewed based on the screen in which each 3D file format is implemented under the same conditions. This study is expected to be helpful for efficient 3D file format for precise implementation of Web - based Scientific Visualization.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.441-447
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• 2003

In the study, we described on the 3D solid model be made on the AutoCAD haved an effect on the deviation of form as RP manufactures the facetres. The STL file improved the deviation of form as the facetres value but the deviation of form have the difference a little as the RP system. In result, we ruled the correlation with the 3D solid model and the RP sample manufacturing, with manufacture RP sample according to facetres value in complex shape. And we developed the program which recombination the STL file that we make use of the AutoLISP.