• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.247-256
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• 2014

Purpose : To assess target motion during radiotherapy by quantifying daily setup errors and inter-fractional and intra-fractional movements of pancreatic fiducials. Materials and Methods : Eleven patients were treated via stereotactic body radiotherapy (SBRT) with volumetric modulated arc therapy. Bony setup errors were calculated using cone beam computed tomography (CBCT). Inter-fractional and intrafractional fiducial (seed) motion was determined via cone beam computed tomography (CBCT) projections and orthogonal fluoroscopy. Results : Using an off-line correction protocol, setup errors were 0.0 (-1.7-4.0), 0.3 (-0.5-3.0), and 0.0 (-4.1-6.6) mm for the left-right, anterior-posterior, and superior-inferior directions respectively. Random inter-fractional setup errors in the mean fiducial positions were -0.1, -1.1, and -2.3 mm respectively. Intra-fractional fiducial margins were 9.9, 7.8, and 12.5 mm, respectively. Conclusion : Online inter-fractional and intra-fractional corrections based on daily kV images and CBCT expedites SBRT of pancreatic cancer. Importantly, inter-fractional and intra-fractional motion needs to be measured regularly during treatment of pancreatic cancer to account for variations in patient respiration.

• Journal of the Korean Society for Library and Information Science
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• v.54 no.4
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• pp.27-51
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• 2020

Regional representative libraries are installing joint preservation archives to solve the problem of lack of preservation space in libraries. This study conducted a survey of public library librarians through a questionnaire survey and an FGI method in order to prepare specific operational policies and implementation plans for the Chungnam Library Joint Preservation Archive, which is a regional representative library. Based on this, an operation policy and implementation plan suitable for the common preservation and use of printed and digital data, which is the goal of the Common Preservation Archive, was proposed. As a result of the study, first, the joint preservation library of the Chungnam Library should first transfer books and serials along with ownership in consideration of the condition and demand of the preservation space of participating libraries. Second, it is necessary to establish an operation management system that can be used by all participating libraries in order to quickly and conveniently operate the joint preservation data center and connect it with a cloud-based integrated data management system. Third, a plan for digitizing and archiving data that was judged to be digitized in the Common Preservation Archive was proposed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.327-335
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• 2014

Current volume tables might underestimate or overestimate the volumes of individual trees in a specific region because the tables were made using the data from broad regions within South Korea. Therefore, to solve this problem, this study was conducted to develop local stem volume tables reflecting the local growth pattern and properties using stem taper equations in the regions of Hongcheon and Yeongju. We developed the local stem volume table for Pinus densiflora, which is the widely planted species in South Korea. To derive the most suitable taper equation for estimating the stem volume of region, three models of Max & Burkhart, Kozak and Parresol et al. were applied and their fitness were statistically analyzed by using the Fitness Index, Bias, and Standard Error of Bias. The result showed that there is a significant difference among the three models, and the Fitness Index of the Kozak model was highest compared to the other models. Therefore, the Kozak model was chosen for generating stem taper equation and stem volume tables for P. densiflora. The result from the developed stem volume tables of each region was compared to the current stem volume tables with driven by the data of tree growth obtained throughout the nation. The result showed that there is a significant difference (0.000< ${\alpha}=0.05$) in two regions, Hongcheon and Yeongju, and also there is a significant difference (0.000< ${\alpha}=0.05$) between the two regions.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.593-598
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• 2016

We report on the preparation of reduced graphene oxide (rGO)/single-walled carbon nanotubes (SWNTs) electrodes deposited onto flexible polyethylene terephthalate (PET) via spray coating technique. The highest capacitance value of the unbent rGO/SWNTs electrode was $82Fg^{-1}$ in 1 M $H_2SO_4$ at $100mVs^{-1}$, which decreased to $38Fg^{-1}$ after 500 bending cycle. Further characterization, including galvanostatic charge/discharge measurements and electrochemical impedance spectroscopy (EIS), showed that the rGO/SWNTs electrode retained a well-defined capacitive response after repetitive bending cycle. Overall, the rGO/SWNTs composite electrode showed reasonable electrochemical properties even prolonged bending cycle. Approximately 50% of the initial capacitance for the rGO/SWNTs composite electrode is remained after 500 bending cycle, making the electrode a potential option for flexible energy storage applications.

• Korean Journal of Construction Engineering and Management
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• v.16 no.4
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• pp.70-79
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• 2015

With the rise of the interest in a renewable system, the importance of the Life Cycle Cost Analysis(LCCA), an economic evaluation tool, has been increasing. However, there is an inevitable gap between a real cost and an estimation from LCCA because of the uncertainty of the external environment in real world. As the input variables in an analysis, such as a real discount rate and an energy cost, ares subject to change as time goes by, strategic decision on the current operating system is made depending on the real cost. Current economic evaluation approaches have treated only the fluctuation of input variables without consideration of the flexibility in operation, which has consequently led to the impairment on the reliability of LCCA. Therefore, new approach needs to be proposed to consider both the uncertainty of input variables and operational flexibility. To address this issue, the application of the Real Option to LCCA is presented in this study. Through a case analysis of LCCA of a solar heating system, the limits and current status of LCCA are identified. As a result, quantitative presentation of strategic decisions has been added in the new approach to implement the traditional approach.

• Journal of Korea Water Resources Association
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• v.32 no.5
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• pp.547-555
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• 1999

The economical manufacturing process of fluorescent sediments (FS) which makes use of the understanding of coastal sediment path has been suggested with respect to the Lagrangian viewpoint. First, the fluorescent liquids were made by the mixing of the fluorescent materials, acetone, and xylene. Second, the sediments collected in Gamami beach were desalinized by the freshwater washing, dried indoors to protect the fine-sediment scattering, and classified by the sieve analysis. Finally, the FS which have seven different colors were manufactured by the mixing of fluorescent liquids and prepared sediments. The FS were used to figure out the major sediment supply routes of the intake channel in the YoungKwang nuclear power plant. From the field experiments, it was shown that the sediments were suspended and dispersed by the strong seasonal NW wind and the tide, and the sediments in suspension were flowing into the intake channel due to very strong suction speed. All the FS injected in stations were detected in the channel sampling points, thus we concluded that the sediments in suspension and dispersion were flowing into the intake channel from all directions in adjacent coastal zone.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1123-1128
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• 1996

A clinical study was performed on 152 cases of surgical esophageal disease treated by the Department of Thoracic & Cardiovascular Surgery of Korea University Hospital from Jan. 1989 through July 1994. The most common esophageal disease was cancer which was seen in 73 cases (48%) among 152 cases. All were treated surgically' 52 patients (71%) were managed by curative or palliative resection with reconstruction and feeding gastrostomy or jejunostomy, otherwise Celestine tube insertion was performed on the remaining 21 patients for palliatio'n. Esophageal leiomyoma occurred in 6 cases(3.9%), among them 1 case was performed with trio recoscopic enucleation . Achalasia were in 7 cases (4.6%) and was treated with modified Heller's m otomy and with Belsey Mark IV operation. Diverticulum were in 11 cases (7.2%). Esophageal stricture occurred in 20 cases (14.1 %) and 17 of 20 cases were managed with bypass surgery. Esophageal perforation was seen in 20 cases, its cause was instrumental trauma in 7 cases, stab wound in 4 cases, foreign body in 4 cases, spontaneous perforation in 3 cases, and others 1 case Other disease including congenital lesion was seen In 1 Scases.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.2
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• pp.55-61
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• 2010

The device with tantalum silicide heater were bonded by Ag paste and Au SBB(Stud Bump Bonding) onto the Au coated substrate. The shear test after Au ABB and the thermal performance under current stressing were measured. The optimum condition of Au SBB was determined by fractured surface after die shear test and $350^{\circ}C$ for substrate, $250^{\circ}C$ for die during flip chip bonding with bonding load of about 300 g/bump. With applying 5W through heater on the device, the maximum temperature with Ag paste bonding was about $50^{\circ}C$. That with Au SBB on Au coated Si substrate showed $64^{\circ}C$. The difference of maximum temperatures is only $14^{\circ}C$, even though the difference of contact area between Ag paste bonding and Au SBB is by about 300 times and the simulation showed that the contact resistance might be one of the reasons.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.184-192
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• 2018

In this study was implemented to develop tree stem weight prediction equation of Larix kaempferi in central region by selecting a standard site, taking into account of diameter and position of the local trees. Fifty five sample trees were selected in total. By utilizing actual data of the sample trees, 11 models were compared and analyzed in order to estimate four different kinds of weights which include fresh weight, ovendry outside bark weight, ovendry inside bark weight and merchantable weight. As to estimate its weight, the study has classified its model according to three parameters: DBH, DBH and height, and volume. The optimal model was chosen by comparing the performance of model using the fit index and standard error of estimate and residual distribution. As a result, the formula utilizing DBH (Variable 1) is $W=a+bD+cD^2$ (3) and its fit index was 90~92%. The formula for DBH and height (Variable 2) is $W=aD^bH^C$ (8) and its fit index was 97~98%. In summation, Variable 2 model showed higher fitness than Variable 1 model. Moreover, fit index of formula for total volume and merchantable volume (W=aV) showed high rate of 98~99%, as well as resulting 7.7-17.5 with SEE and 8.0-10.0 with CV(%) which lead to predominately high fitness in conclusion. This study is expected to provide information on weights for single trees and furthermore, to be used as a basic study for weight of stand unit and biomass estimation equations.

• Molecular & Cellular Toxicology
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• v.5 no.2
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• pp.120-125
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• 2009

Alaria esculenta is a brown seaweed found in the Arctic. This study investigated the protective effect of A. esculenta extract (AEE) against oxidant-mediated injury and its mode of action in RAW264.7 macrophages. The methyl thiazolyl tetrazolium (MTT) assay showed that $H_2O_2$ treatment reduced cell viability, whereas AEE protected cells from $H_2O_2$-mediated cytotoxicity in a dose-dependent manner. Because heme oxygenase-1 (HO-1) is known to protect cells against oxidative damage, we investigated the effect of AEE on HO-1 gene expression and HO enzyme activity. The protective effect of AEE against $H_2O_2$-induced injury was correlated with increased HO enzyme activity. AEE also induced HO-1 mRNA and protein expression, as determined RT-PCR and Western blotting, respectively. To characterize the mechanisms by which AEE induces HO-1 gene expression, we examined the effect of AEE on the nuclear translocation of NF-E2-related factor-2 (Nrf2) and Akt phosphorylation. AEE treatment activated upstream signaling for HO-1 gene expression, including the nuclear translocation of Nrf2 and Akt phosphorylation. Collectively, these results suggest that AEE has anti-oxidant activity that is mediated, at least in part, via the activation of Nrf2 and Akt and the subsequent induction of HO-1 gene expression.