• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2313-2318
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• 2003

By means of flexible forming processes in sheet metal manufacturing it is possible to produce parts of complex geometry within short manufacturing time. These procedures are suitable especially for prototyping or adjustment of deformation. Here formative procedures like laser forming are increasingly important, because they make the large-scale-like production of the prototypes with the required materials possible. High accuracy and reproducibility of the products is the precondition of the production. Due to the lack of a forming tool, complex geometries can hardly be manufactured within tolerances. To overcome this problem an automatic closed loop control system for the adjustment of deformations has been developed. An important element of the closed loop control system is the definition of a suitable irradiation strategy for laser forming. For the determination of the irradiation strategy a lot of influences must be taken into consideration from the field of material, geometry and laser. In this paper the improved closed loop control system and the development of an irradiation strategy for 4 mm deep buckles in an ALMgSi1 sheet will be represented. This system can be used e.g. in the automated adjustment of hail damage in car bodies or deformation by heat treatment.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2359-2366
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• 2022

Selecting graphite grades with superior irradiation characteristics is important task for designers of graphite moderation reactors. To provide reference information and data for graphite selection, the effects of irradiation on three fine-grained, iso-molded nuclear grade graphites, ETU-10, IG-110, and NBG-25, were compared based on irradiation-induced changes in volume, thermal conductivity, dynamic Young's modulus, and coefficient of thermal expansion. Data employed in this study were obtained from reported irradiation test results in the high flux isotope reactor (HFIR)(ORNL) (ETU-10, IG-110) and high flux reactor (HFR)(NRL) (IG-110, NBG-25). Comparisons were made based on the irradiation dose and irradiation temperature. Overall, the three grades showed similar irradiation-induced property change behaviors, which followed the historic data. More or less grade-sensitive behaviors were observed for the changes in volume and thermal conductivity, and, in contrast, grade-insensitive behaviors were observed for dynamic Young's modulus and coefficient of thermal expansion changes. The ETU-10 of the smallest grain size appeared to show a relatively smaller VC to IG-110 and NBG-25. Drastic decrease in the difference in thermal conductivity was observed for ETU-10 and IG-110 after irradiation. The similar irradiation-induced properties changing behaviors observed in this study especially in the DYM and CTE may be attributed to the assumed similar microstructures that evolved from the similar size coke particles and the same forming method.

• Nuclear Engineering and Technology
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• v.51 no.3
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• pp.769-775
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• 2019

The tensile strength of irradiated 3C-SiC, SiC with artificial point defects, SiC with symmetric tilt grain boundaries (GBs), irradiated SiC with GBs are investigated using molecular dynamics simulations at 300 K. For an irradiated SiC sample, the tensile strength decreases with the increase of irradiation dose. The Young's modulus decreases with the increase of irradiation dose which agrees well with experiment and simulation data. For artificial point defects, the designed point defects dramatically decrease the tensile strength of SiC at low concentration. Among the point defects studied in this work, the vacancies drop the strength the most seriously. SiC symmetric tilt GBs decrease the tensile strength of pure SiC. Under irradiated condition, the tensile strengths of all SiC samples with grain boundaries decrease and converge to certain value because the structures become amorphous and the grain boundaries disappear after high dose irradiation.

• Journal of Radiation Industry
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• v.4 no.1
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• pp.47-51
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• 2010

Centipedegrass is a warm season turfgrass in the world. Chlorogenic acid (CA) is one of the important compounds present in the leaf of centipedegrass and already known as an antioxidant, CA has become a key resistance against insect pests and bacteria pathogens of agricultural and horticultural plants during seedling stage. Furthermore, CA is accumulated by abiotic stress such as an UV irradiation. In present study, we investigated enhancement of the level of CA upon gamma irradiation in centipedegrass. The high performance liquid chromatography (HPLC) data analysis showed an approximately increasing of the CA levels from among the irradiated samples. However, plants irradiated at 50 Gy showed a constant increase in the CA level (0.0066 to $0.114mg\;ml^{-1}$ and 0.0258 to $0.2211mg\;ml^{-1}$, respectively) from $3^{rd}$ to $15^{th}$ day among one and three month irradiated plants compared to control. The present study, indicates an increase in the CA level upon gamma irradiation, suggests strategy for conferment of strong resistance in seedling stage plants by gamma irradiation as simplicity and cheaply method.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.75-80
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• 2009

Composition changes of swine manure and the effects on MAP ($MgNH_4PO_46H_2O$) crystallization by microwave irradiation were examined. The concentration of ${PO_4}^{3-}$ was increased within a fixed period of time and then decreased, but $NH_4$-N was reduced continuously during microwave irradiation. Concentration of ${PO_4}^{3-}$ was started to reduce just from the point of foam formation during microwave irradiation, and the temperature at that time was always $49^{\circ}C$ irrespectively to microwave irradiation rate. Inorganic carbon was reduced with microwave irradiation, but soluble organic carbon (TOCs) was increased proportionally. Crystallization rate under conditions of non-microwave irradiation, irradiation up to $93^{\circ}C$ and $48^{\circ}C$ was 87.8%, 87.3% and 98.5%, respectively, showing 10% enhancement when irradiated up to $48^{\circ}C$. However, removal efficiency of ammonia nitrogen was proportional to the microwave irradiation rate or duration, obtaining 2.5%, 4.5% and 10.2%, respectively. Based on these results, it would be a useful strategy to irradiate microwave up to $49^{\circ}C$ to enhance MAP crystallization rate by changing the ionic pattern of nutrients in the manure. Meanwhile, provision of enough microwave irradiation rate might be needed to achieve high $NH_4$-N removal.

• Journal of Yeungnam Medical Science
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• v.7 no.2
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• pp.109-114
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• 1990

The basic strategy of irradiation is to deliver a dose to the cancer that is high enough to make cancer cells incapable of reproduction, while keeping the doses to the various healthy tissues below tolerable levels. In order to improve local control and survival, as a boost therapy after external radiotherapy, high dose rate transcatheteric irradiation using remote control afterloading system(RALSTRON-20B) was used for twelve patients with head and neck cancers. Present results showed complete remission of cancer in 9 out of 12 patients without treatment related complications. Although this procedure is easy to operate, well trained skillful hand is essential for good results. Furthermore our experience suggested that meticulous treatment planning should be developed for better results.

• Radiation Oncology Journal
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• v.37 no.1
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• pp.1-12
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• 2019

Despite recent innovation in treatment techniques and subsequently improved outcomes, the majority of glioblastoma (GBL) have relapses, especially in locoregional areas. Local re-irradiation (re-RT) has been established as a feasible option for recurrent GBL of all ages with safety, tolerability, and effectiveness both in survival and quality of life regardless of fractionation schedule. To keep adverse effects under acceptable range, cumulative dose limit in equivalent dose at 2 Gy fractions by the linear-quadratic model at α/β = 2 for normal brain tissue (EQD2) with narrow margin should be observed and single/hypofractionated re-RT should be undertaken very carefully to recurrent tumor with large volume or adjacent to the brainstem. Promising outcome of re-operation (re-Op) plus re-RT (re-Op/RT) need to be validated and result from re-RT with temozolomide/bevacizumab (TMZ/BV) or new strategy is expected. Development of new-concept prognostic scoring or risk group is required to select patients properly and make use of predictive biomarkers such as O(6)-methylguanine-DNA methyltransferase (MGMT) promotor methylation that influence outcomes of re-RT, re-Op/RT, or re-RT with TMZ/BV.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.4
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• pp.282-288
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• 2020

Radiation prosthetic stent is defined as the customized oral devices which serve for an efficient administration of radiation dose to the affected areas or a minimizing the unnecessary irradiation to surrounding normal tissues during maxillofacial cancer radiotherapy. Since the use of stents is individualized, a close collaboration among radiotherapist, surgeon and prosthodontist is essential thereby which helps in limiting the post-therapy morbidity as well as the stable oral rehabilitation. In this report, two customized stents (bolus carrier and tongue depressing) were fabricated and applied to patient undergone irradiation for soft palate and tongue carcinoma selectively. Multidisciplinary approach can be a proper strategy and recommended for control the sequel of post-irradiation.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.487-487
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• 2011

Recently graphene has emerged as a fascinating 2D system in condensed-matter physics as well as a new material for the development of nanotechnology. The unusual electronic band structure of graphene allows it to exhibit a strong ambipolar electric field effect with high mobility. These properties lead to the possibility of its application in high-performance transparent conducting films (TCFs). Compared to indium tin oxide (ITO) electrodes, which have a typical sheet resistance of ${\sim}60{\Omega}$/sq and ~85 % transmittance in the visible range (400?900 nm), the CVD-grown graphene electrodes have a higher/flatter transmittance in the visible to IR region and are more robust under bending. Nevertheless, the lowest sheet resistance of the currently available CVD graphene electrodes is higher than that of ITO. Here, we report an ingenious strategy, irradiation of MeV electron beam (e-beam) at room temperature under ambient condition, for obtaining size-homogeneous gold nanoparticle decorated on graphene. The nano-particlization promoted by MeV e-beam irradiation was investigated by transmission electron microscopy, electron energy loss spectroscopy elemental mapping, and energy dispersive X-ray spectroscopy. These results clearly revealed that gold nanoparticle with 10 ~ 15 nm in mean size were decorated along the surface of the graphene after 1.5 MeV-e-beam irradiation. A chemical transformation and charge transfer for the metal gold nanoparticle were systematically explored by X-ray photoelectron spectroscopy and Raman spectroscopy. This approach advances the numerous applications of graphene films as transparent conducting electrodes.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.262-262
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• 2010

We introduce a novel and efficient strategy for producing free-standing functional films via photo-crosslinking and electrostatic layer-by-layer (LbL) assembly, which can allow the buildup of hydrophilic multilayers onto hydrophobic surfaces. Hydrophobic multilayers were deposited on ionic substrates by a photo-crosslinking LbL process using photo-crosslinkable polymers. The photo-crosslinked surface was converted to an anionic surface by excess UV light irradiation. This treatment allowed also the stable adhesion between metal electrode or cationic polyelectrolyte and hydrophobic multilayers. After dissolving the ionic substrates in water, the formed free-standing films exhibited unique functionalities of inserted components within hydrophobic and/or hydrophilic multilayers.