• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1429-1433
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• 2001

This study provides electron microscopic evidence for the presence of cellulosome-like structures on the cell surface of Ruminococcus albus F-40. Electron microscopy showed that clusters of tightly packed spherical particles were located on the cell surface of R. albus. The protuberant structures present mainly on the bacterial surface and also bound to the cellulose substrate appeared to be the site of cellulosome-like structures. From the evidence presented, we suggest that the structures described here might be a characteristic feature of some ruminal cellulolytic bacteria.

• Journal of the Korean Society of Safety
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• v.31 no.5
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• pp.102-108
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• 2016

This paper presents a new strength method of underground box structures under additional surface load. An L-bracing using pre-flexed steel member threads called the "Pre-flex strength method" is used to improve capacity of the RC box structure under earth pressure due to additional surface load. The pre-flexed steel member is fixed the top and bottom of the structure after chemical anchor was installed by drilling hole on the box structure. The structural performance was evaluated analytically. 3 types of underground RC box structure were used; $2.0m{\times}2.0m$, $3.0m{\times}3.0m$ and $4.0m{\times}4.0m$. For the performance evaluation, structure analysis were performed on moment and shear resisting structures with and without pre-flex strength method. Numerical results confirmed that the proposed strength member system installed on underground RC box structures enhanced the strength capacity. The feasible region of the proposed pre-flex strength method in accordance with the earth pressure due to additional surface depth was evaluated.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.2
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• pp.197-203
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• 2021

Mechanical structures of military equipment have been mainly applied with black oxide coating due to the limitation of surface treatment thickness. However, the mechanical structures applied by the black oxide coating treatment is constantly being corroded by calcium chloride and humidity. Since this can cause serious problems in the operation of equipment, a review to improve surface treatment and corrosion resistance is required. Therefore, in this study, surface treatment methods that can enhance corrosion resistance were selected and corrosion resistance performance was verified through experiments describing harsh field conditions. Thus, applying a proven surface treatment method to future military equipment will prevent corrosion.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.3
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• pp.225-230
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• 2016

Since the development of anodic aluminum oxide (AAO), extensive studies have been conducted ranging from fundamental research to the applications of AAO. Most of the research on AAO structures have focused on well-aligned nanoporous structures fabricated under specific conditions. This study investigated fabricable AAO structures with anodization performed with various temperatures, electrical potentials, and basal plane surfaces. As a result, nanoporous and nanofibrous structures were fabricated. The nanopores were formed at a relatively lower temperature and potential, and the nanofibers were formed at a relatively higher temperature and potential regardless of the basal plane surface. The shape of the base surface was found to influence the structural arrangement in nanoporous morphologies. These interesting findings relating to new morphologies have the potential to broaden the possible applications of AAO materials.

• International Journal of Automotive Technology
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• v.3 no.3
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• pp.117-122
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• 2002

Joint stiffness can affect the vibration characteristics of car body structures. Therefore, it should be included in vehicle system model. In this paper, a numerical approximation of joint stiffness is presented considering joint flexibility of thin walled beam-jointed structures. Using the proposed method, it is possible to optimize joint structures considering the change of section shapes in vehicle structures. The numerical approximation of joint stiffness is derived using the response surface method in terms of beam section properties. The study shows that joint stiffnesses can be effectively determined in designing vehicle structures.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.343-343
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• 2011

ZnO has been introduced as one of the good candidates for next generation opto-electronics. Recently, ZnO is known to be suitable for the transparent electrode in organic solar cells and light emitting devices. The contact with n-type organic material has been studied due to the n-type properties of ZnO. However, the surface of ZnO has shown different electronic property with respect to its surface orientation. Therefore, it is presumed that there are differences in the interfacial electronic structures between organic materials and ZnO with different orientation. Therefore, it is required to classify the interfacial electronic structures according to the surface orientation of ZnO. In this study, we measured the interfacial electronic structures between the ZnO substrate having various orientations and a typical n-type organic material, tris-(8-hydroxyquinoline) aluminum (Alq3). In-situ x-ray and ultraviolet photoelectron spectroscopy measurements revealed the interfacial electronic structures. We found the changes in the electronic structures with respect to the orientation of ZnO substrate and it could be used to improve the contact between ZnO and Alq3.

• Korean Journal of Optics and Photonics
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• v.13 no.2
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• pp.166-170
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• 2002

Reflectors for reflective LCDs must be designed to be able to control the direction of the image and the viewing angle range for optimal display. In this paper, we tried to optimize the reflector for reflective LCDs. The conventional surface structures showed many defects and problems. Therefore we made efforts to improve the surface structures of the conventional reflectors through both a theoretical approach and analytic work. As a result, we proposed surface structures which showed almost uniform reflectance within the viewing angle range specified by a user even at any oblique incidence. By using Beckmann's equations, we could check the reflective property of the proposed surface structures.

• Applied Science and Convergence Technology
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• v.25 no.5
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• pp.92-97
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• 2016

Surface erosion using focused ion beam irradiation is the most promising technology for the realization of micro/nanofabrication. However, accurate fabrication of predefined structures is still challenging. This article introduces a single step surface driving method to fabricated predefined curved structures. The previously reported multi step surface driving method (MSDM) has been modified so that a single ion dose profile can be used instead of multiple ion dose profiles. Experimental realization of the method is presented with the fabrication of predefined curved surfaces as well as reference to surface propagation theory. For the purpose of verification, simulations are performed on the basis of a sound mathematical model.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.14 no.1
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• pp.71-80
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• 1984

The author has studied each landmark for successful interpretation in the radiograph of the head that have the complex anatomic structures, using panoramic radiograph, postero-anterior cephalometric radiograph, lateral cephalometric radiograph, Waters' radiograph of the skull. The anatomic structures of the human dry skull attached by radiopaque materials were taken radiographs and analysed comparatively. The results were as follows: 1. The overall anatomic structures of the mandible showed sharp images in the panoramic radiograph than other radiographs with relatively less distortion, superimposition, blurring of the image. 2. The anatomic structures were situated on sagital plane of the skull showed blurred images in panoramic radiograph than other radiographs. 3. The anatomic structures which were situated on the basal portion of the skull showed blurred and secondary images in the panoramic radiograph than other radiographs. 4. In the panoramic radiograph, the lower 3rd portion of the orbit appeared to be superimposed with the superior portion of the maxillary sinus and the medial and lateral surface of the nasal cavity showed extensively superimposition of the orbit and the maxillary sinus, which images showed blurring. 5. The inferior surface and posterior surface of maxillary sinus showed to be good image in the panoramic radiograph than other radiographs. 6. In the panoramic radiograph, line of maxillary bone between lateral pterygoid plate, line of maxillary bone between zygomatic bone showed distinct image with another structures.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.270-270
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• 2013

We have investigated the self-assembled structures of glutaric acid (HOOC-(CH2)3-COOH) on the Cu(110) surface as a function of coverage using Scanning Tunneling Microscopy (STM). At low coverage, glutaric acid molecules diffuse freely on Cu(110) surface at room temperature, thus they can't form ordered structures at this coverage. However, when we scanned the same area several times, novel structures have been created during scanning due to the field-induced self-assembly. Also, the induced structures are quite stable during continuous scanning process. At 0.25 ML, glutaric acid adsorbs as a bi-glutarate (-OOC(CH2)3-COO-) after annealing to 450 K producing a racemic conglomerate of coexisting mirror domains. Although the molecule is achiral, it forms chiral domains on the surface from adsorption-induced asymmetrization. At 0.5 ML coverage, zigzag structure is observed, and still gltutaric acid adsorbs as a bidentate configuration. This bi-glutarate structure is stable until 650. Finally, at 1ML, glutaric acid adsorbs as a mono-glutarate at room temperature forming close packed structures.