• Journal of Korean Neurosurgical Society
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• v.62 no.5
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• pp.577-585
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• 2019

Objective : Comparing the effects of magnetically controlled growing rod (MCGR) and traditional growing rod (TGR) techniques on the sagittal plane in the treatment of early-onset scoliosis (EOS). Methods : Twelve patients were operated using dual MCGR technique in one center, while 15 patients were operated using dual TGR technique for EOS in another center. Patients' demographic characteristics, complications and radiological measurements such as cobb angle, thoracic kyphosis, lumbar lordosis, T1-S1 range (mm), proximal junctional angle, distal junctional angle, sagittal balance, coronal balance, pelvic incidence, sacral slope and pelvic tilt were assessed and compared in preoperative, postoperative and last follow-up period. Results : Age and sex distributions were similar in both groups. The mean number of lengthening in the MCGR group was 12 (8-15) and 4.8 (3-7) in the TGR group. Two techniques were shown to be effective in controlling the curvature and in the increase of T1-S1 distance. In TGR group, four patients had rod fractures, six patients had screw pull-out and four patients had an infection, whereas three patients had screw pull-out and one patient had infection complications in the MCGR group. Conclusion : There was no significant difference between the two groups in terms of cobb angle, coronal and sagittal balance and sagittal pelvic parameters. MCGR can cause hypokyphosis and proximal junctional kyphosis in a minimum 2-year follow-up period. The implant-related complications were less in the MCGR group. However, larger case groups and longer follow-up periods are required for the better understanding of the superiority of one method on other in terms of complications.

• Journal of Korean Neurosurgical Society
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• v.63 no.2
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• pp.228-236
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• 2020

Objective : It can be assumed that the progression of scoliosis in the juvenile period will increase the asymmetry in the rib cage, and thus will contribute to an increase in the breast asymmetry (BA) in the future. We are looking for answers to the questions; "How will the breasts look with respect to each other and what is the possibility of developing BA in the early follow-up period following the early surgical treatment and final fusion surgery of juvenile idiopathic scoliosis (JIS)?" For this reason, in this study, we aimed to evaluate the breast asymmetries of patients in the period after the final fusion. Methods : Following growing rod treatment, final fusion was achieved in 12 females with JIS. We used the anthropomorphic measurement of the modified BREAST-V formula to assess whether there was an asymmetry between the breasts after an average of 4.8 years (2-11) following final fusion. Results : In comparison, the mean volume of the left breast (222.4 mL [range, 104.1-330.2]) was larger than the mean volume of the right breast volume (214.5 mL [range, 95.2-326.7]) (p=0.034). The left breast was larger in 75% of the patients. BA was observed in 50% of the patients. No correlation was detected between the Cobb angle of the patient after final fusion and BA (p=0.688). Conclusion : In the late follow-up period, BA was detected in 50% of the patients with JIS who achieved final fusion after treatment with growing rod. In majority of the patients, left breast was larger. The patients with JIS and their families can be informed prior to the operation about the probability of BA seen in the follow-up period after fusion.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.3
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• pp.250-260
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• 1995

In general, a sintered rod is used as a feed in the growth of crystals by the floating zone(FZ) method. The sintering condition of the feed rod affected the stability of molten zone because it influenced the interface shape between the feed and the melt during the crystal growth. In this study, rutile and ruby crystals were chosen as samples to analyze the effect of the microstructures of the feed rods. In sintering of the feed rod for the growth of rutile and ruby single crystals, the difference of grain size between the inner and the outer region of the feed rod increased with the sintering temperature and dwelling time. As a result, it altered melting behavior of the feed. The uniform grain size of the sintered rod was necessary for the optimum growing condition of crystals. The effect of pores in the feed rod was not a dominant factor to grow crystals by the FZ method, which was confirmed by growing crystals with nonsinterd rods as feeds.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.137-138
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• 2009

There is a growing interest to replace the commercial steels with non-heat treated steels, which does not involve the spheroidization and quenching-tempering treatment in the steel-wire industry production. However, non-heat treated steels should satisfy high strength and good formability without performing heat treatment. Therefore, it is important to investigate optimum materials showing a good combination of strength and formability after the cold drawing process. In this presentation, non-heat treated steel wire rod produced by POSCO will be introduced and discussed on detail technical concepts.

• Journal of Photoscience
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• v.9 no.2
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• pp.47-50
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• 2002

Raft is a distinctive membrane domain enriched in a certain class of lipids, cholesterol, and proteins observed on the plasma membrane. Growing evidence has revealed that such membrane domains play key roles in signal transduction, fertilization, development, transmitter release, and so on. Recently, we have isolated raft-like detergent-resistant membrane (DRM) fraction from bovine photoreceptor rod outer segments. Transducin and its effecter, cGMP-phosphodiesterase, elicited stimulus-dependent translocation between detergent-soluble membrane and DRM. This suggested potential importance of such distinct membrane domains in vertebrate phototransduction. Here, we will discuss physiological meaning of the translocation of major components of cGMP cascade to raft-like membrane in phototransduction. We would like to propose a hypothesis that raft-like membrane domains on the disk membrane are the place where cGMP cascade system could be quenched.

• Applied Science and Convergence Technology
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• v.27 no.2
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• pp.38-41
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• 2018

We demonstrate the growth of a sheet-like ZnO membrane on ZnO nano rod layers. The growth process is composed of 3 steps of ZnO seed formation, ZnO nano rod growth and sheet-like ZnO membrane formation on those nano rods. To confirm the fundamental growth mechanism, the lattice structures of each step were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) measurement. Analysis of the relation between the texture coefficient and the surface shape of the ZnO membrane on the ZnO nano rods shows that the surface morphology of ZnO nano structures can be controlled using the temperature of the growing solution and the concentration of the chemical solution.

• Journal of the Korean Ceramic Society
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• v.27 no.8
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• pp.1050-1054
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• 1990

Rutile(TiO2) single crystals were grown by FZ method. Feed rod was sintered in the longitudinal tube-shaped furnace at 135$0^{\circ}C$ and optimum growth condition was growth rate 5-8mm/hr, rotation rate 30-40rpm. When crystal was growing, atomosphere was oxidized condition, and grown single crystal was annealed at 110$0^{\circ}C$. The rutile single crystals were oriented to [001] direction and color change of single crystals were related to atmosphere, and difference of electric conductivity and resistance was due to the fact above.

• Tribology and Lubricants
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• v.38 no.6
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• pp.227-234
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• 2022

Recently, the demand for improving energy efficiency has rapidly increased because of the growing concerns over environmental issues. In this work, the tribo-test and simulation for the initial wear and lubrication performance were performed for the piston pin in the small end system of the connecting rod of a marine engine, to obtain useful data for improving the efficiency of marine engine systems. In addition, a diamond-like carbon (DLC) coating was applied to the piston pin to explore feasibility of eliminating the bush used in the system. The initial wear and lubrication characteristics between the uncoated piston pin and bush were compared with that between the DLC-coated piston pin and connecting rod in the tribo-test. The simulation for the wear and lubrication performance according to the wear progression was conducted based on the data obtained from the test. The wear characteristics were quantitatively assessed by the wear depth and wear volume, and the lubrication performance was characterized with the change of pressure and minimum oil film thickness with respect to the crank angle. It was found that the DLC-coated piston pin may provide better initial wear characteristics and lubrication performance. The results of this work may provide fundamental information for marine engines with improved efficiency.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.6
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• pp.3-10
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• 2018

This paper described the shear strengthening effect by deviator location in pre-damaged reinforced concrete (RC) beams strengthened with externally post-tensioning steel rods. Three reinforced concrete beams as control beam and eight post-tensioned beams using external steel rods were tested to fail in shear. The externally post-tensioning material was a steel rod of 22 mm diameter, and it had a 655 MPa yield strength and an 805 MPa tensile strength. Specimens depend on multiple variables, such as the number of deviators, location of deviator, and load pattern. The pre-damaged loads up to about 2/3 of ultimate shear capacities were applied to specimens using displacement control and the diagonal shear crack just occurred at these loading levels. And then, the post-tensioning up to when a strain of steel rod reaches about $2000{\mu}{\varepsilon}$ was continuously applied to beam. A displacement control was changed to a load control during post-tensioning. The post-tensioning resulted in increase of load-carrying capacity and restoration of existing deflection. Also, it prevented the existing diagonal cracks from excessively growing. Two deviators effectively improved the load capacity when compared with in case of test which one deviator at mid-span installed. When deviators were located near region which the diagonal crack occurred on, the strengthening impact by post-tensioning was greater.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.543-547
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• 1991

An alkalophilic microorganism, SH-8, was isolated from soil samples. It was a Grampositive, catalase-positive, spore-forming and motile rod which was capable of growth in aerobic condition at the initial pH 9.0 or above up to 11.0 and between 15 and $42^{\circ}C$ The characteristics of this strain resembled those of the Bacillus group of bacteria. The mutant, Bacillus sp. SH- 8M, was selected from Bacillus sp. SH-8 by U.V. mutagenesis and was able to grow at pH 6.9 up to 11.0. These two strains will be suitable for the comparative study on growth and enzyme production at various pH conditions.