• Journal of Yeungnam Medical Science
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• v.11 no.1
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• pp.55-62
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• 1994

The use of intraoperative application of Mitomycin C at the filtration site has been known to improve the surgical outcome in glaucomatous eyes with high risk for failure of trabeculectomy. The author performed trabeculectomies with intraoperative Mitomycin C on 25 eyes of 20 patients with poor surgical prognosis to study the efficacy and safety of this technique in glaucomatous patients with high risk for failure of trabeculectomy. After the preparation of a scleral flap, 0.2mg/ml solution of Mitomycin C was applied between Tenon's capsule and the sclera for 2 minutes. The exposed area was then irrigated with 200 ml of balanced salt solution. The follow-up period was from 1 to 7 months (mean 3.8 months). The mean preoperative intraocular pressure (IOP) was $38.6{\pm}6.6mmHg$. The mean final postoperative IOP was $11.7{\pm}3.8mmHg$. Twenty three (88%) of the 25 eyes were successfully controlled with the IOP of less than or equal to 20 mmHg without glaucoma medication. There were early postoperative complications of hyphema in 5 eyes (20%), shallow anterior chamber in 4 eyes(16%), punctate keratopathy in 3 eyes (12%), aqueous leaking from conjunctival wound in 2 eyes (8%), encapsulated bleb in 1 eye (4%) and choroidal detachment in 1 eye (4%), and 4 eyes had long term hypotony lasting more than 2 months. Although Mitomycin C is simple to use and effective adjunct to trabeculectomy, further study will be needed to determine the mechanism of action, indication, dosage and optimal exposure time of Mitomycin C.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.3
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• pp.192-199
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• 2013

The Tandong-cheon stream is a 7.4 km long small urban stream that passes through Daeduk Science Town in Daejeon Korea. Despite the stream has great potential as an educational and recreational site due to its central location in the science town and science museums nearby, environmental aspect especially for water quality has not been evaluated properly. Through field survey, major pollution sources of the stream were identified and effect of water quality improvement alternatives were evaluated using a QUAL2K water quality model for the stream. The study indicated that controlling major pollution sources of the stream alone may not be sufficient for reaching the water quality target. Therefore, additional pollution control methods are necessary. We applied the developed model to evaluate the effects of a constructed wetland on the terrace land, and analyzed whether the water quality target can be met at the outlet of the stream. It is expected that this study would provide a good reference for environmentally sound management of small urban streams in Korea.

• Korean Journal of Materials Research
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• v.33 no.1
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• pp.15-20
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• 2023

'Tracers' are bullets that emit light at the backside so that the shooter can see the trajectory of their flight. These light-emitting bullets allow snipers to hit targets faster and more accurately. Conventional tracers are all combustion type which use the heat generated upon ignition. However, the conventional tracer has a fire risk at the impact site due to the residual flame and has a by-product that can contaminate the inside of the gun and lead to firearm failure. To resolve these problems, it is necessary to develop non-combustion-type tracers that can convert heat to luminance, so-called 'thermoluminescence (TL)'. Here, we highly improve the thermoluminescence properties of MgB₄O₇ through co-doping of Dy³⁺+Ce³⁺ and Dy³⁺+Na⁺. The presence of doping materials (Dy³⁺, Ce³⁺, Na⁺) was confirmed by XPS (X-ray photoelectron spectroscopy). The as-synthesized co-doped MgB₄O₇ was irradiated with a specific radiation dose and heated to 500 ℃under dark conditions. Different thermoluminescence characteristics were exhibited depending on the type or amounts of doping elements, and the highest luminance of 370 cd/m² was obtained when Dy 10 % and Na 5 % were co-doped.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3915-3920
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• 2014

Background: Hepatocellular carcinoma (HCC) is a dismal tumor with a high incidence, prevalence and poor prognosis and survival. Management of HCC necessitates multidisciplinary clinics due to the wide heterogeneity in its presentation, different therapeutic options, variable biologic behavior and background presence of chronic liver disease. We studied the different prognostic factors that affected survival of our patients to improve future HCC management and patient survival. Materials and Methods: This study is performed in a specialized multidisciplinary clinic for HCC in Kasr El Eini Hospital, Cairo University, Egypt. We retrospectively analyzed the different patient and tumor characteristics and the primary mode of management applied to our patients. Further analysis was performed using univariate and multivariate statistics. Results: During the period February 2009 till February 2013, 290 HCC patients presented to our multidisciplinary clinic. They were predominantly males and the mean age was $56.5{\pm}7.7years$. All cases developed HCC on top of cirrhosis that was mainly due to HCV (71%). Most of our patients were Child-Pugh A (50%) or B (36.9%) and commonly presented with small single lesions. Transarterial chemoembolization was the most common line of treatment used (32.4%). The overall survival was 79.9% at 6 months, 54.5% at 1 year and 22.4% at 2 years. Serum bilirubin, site of the tumor and type of treatment were the significant independent prognostic factors for survival. Conclusions: Our main prognostic variables are the bilirubin level, the bilobar hepatic affection and the application of specific treatment (either curative or palliative). Multidisciplinary clinics enhance better HCC management.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.2
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• pp.163-169
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• 2015

In many nuclear power plant sites in Korea, high density storage racks were installed in the spent fuel pool to expand the spent fuel storage capacity. Nevertheless, the capability of the Hanbit nuclear site will be saturated by 2024. Also, 10 NPPs will reach their design life expiration date by 2029. In the case of the US, SFPI (Spent Fuel Pool Island) operated temporarily as a spent fuel storage option before spent nuclear fuels were transported to an interim storage facility or a final disposal facility. As a spent fuel storage option after shutdown during decommissioning, the SFPI concept can be expected to have the following effects: reduced occupational exposure, lower cost of operation, strengthened safety, and so on. This paper presents a case study associated with the regulations, operating experiences, and systems of SFPI in the US. In conclusion, the following steps are recommended for applying SFPI during decommissioning in Korea: confirmation of design change scope of SFPI and expected final cost, the submission of a decommissioning plan which is reflected in SFPI improvement plans, safety assessment using PSR, application of an operating license change for design change, regulatory body review and approval, design change, inspection by the regulatory body, education and commissioning for SFPI, SFPI operation and periodic inspection, and dismantling of SFPI.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.2
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• pp.155-170
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• 2020

In this paper, a risk management system applicable to NATM tunneling projects is proposed. After investigating case histories in NATM tunnel collapse, this paper analyzes the potential risk factors and their corresponding risk events during NATM tunnel construction. The risk factors are categorized into three groups: geological, design and construction risk factors. The risk events are also categorized into four types: excessive deformation, excessive deformation with subsidence, collapse inside tunnels, and collapse inside tunnels with subsidence. The paper identifies risk scenarios in consideration of the risk factors and proposes a risk analysis/evaluation method for the NATM tunnel risk scenarios. Based on the evaluation results, the optimal mitigation measure to handle the risk events is suggested. In order to effectively facilitate a series of risk management processes, it is necessary to develop a risk register and a management ledger for risk mitigation measures that are customized to NATM tunnels. Lastly, the risk management for an actual NATM tunnel construction site is performed to verify the validity of the proposed system.

• Journal of Convergence for Information Technology
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• v.11 no.1
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• pp.136-142
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• 2021

Open-pit mine development requires continuous management because of topographical changes and there is a risk of accidents if the current status survey is performed directly in the process of calculating the earthwork. In this study, the application of UAV photogrammetry, which can acquire spatial information without direct human access, was applied to open-pit mines development area and analyzed the accuracy, earthwork, and mountain restoration plan to determine its applicability. As a result of accuracy analysis at checkpoint using ortho image and Digital Surface Model(DSM) by UAV photogrammetry, Root Mean Square Error(RMSE) is 0.120 m in horizontal and 0.150 m in vertical coordinates. This satisfied the tolerance range of 1:1,000 digital map. As a result of the comparison of the earthwork, UAV photogrammetry yielded 11.7% more earthwork than the conventional survey method. It is because UAV photogrammetry shows more detailed topography. And result of monitoring mountain restoration showed possible to determine existence of rockfall prevention nets and vegetation. If the terrain changes are monitored by acquiring images periodically, the utility of UAV photogrammetry will be further useful to open-pit mine development.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.742-749
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• 2007

The objective of this study was to develop thinning effect analysis model (TEAM) using individual-tree distance-independent growth model of Pinus koraiensis Stands. The TEAM was designed to analyze thinning effects associated with such thinning prescriptions as the number, timing, intensity, and method of thinnings. To testing TEAM application, stand growth effects were compared with seven scenarios according to thinning prescription plan. In the results, it was possible to estimate the number of trees, height, volume with diameter (DBH) class of individual trees, and average diameter growth, height growth, the number of trees and volume growth per ha of stands. The result of sensitivity analysis on one Pinus koraiensis stand, it was not sure to expect the much more volume at the rotation age by stand density control applying thinning prescription. In the case of thinning, total yield volume has much more $40{\sim}75m^3$ per ha, within 5 cm in average diameter growth and within 1 m in average height growth than thats of non-thinning over increasing stand age. TEAM, as decision making support system, can be used for selecting the thinning prescription trial and determining one of some thinning prescription plan in different site specific stand environments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.160-166
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• 2021

In this study, we aim to develop a scenario for educational utilization of disaster response robots that can be used at fire sites and analyze the effectiveness of scenarios according to robot utilization education. Our scenarios were developed based on direction, reality, and rationality determined through the use of a questionnaire survey distributed to current firefighters. In addition, the educational utilization of disaster response robots and training effectiveness were analyzed through repetitive robot control training by a robot development team, current firefighters, and college students. Robot control was divided into direct control, monitor control, and simulation control, and tests were carried out five times. As a result of the analysis of the robot control test, the average time spent for each group was 28 seconds for college students, followed by development teams (30second) and incumbent firefighters (38second). According to the individual analysis results, firefighters (maximum 35second) in direct control, the development team (maximum 14second) in monitor control, and firefighters (maximum 22second) in simulation control showed the effect of shortening control time. These results show that robot control education and training is necessary for robots to be used more effectively at disaster sites.

• Journal of Mushroom
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• v.21 no.3
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• pp.118-125
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• 2023

We conducted an on-site application study at the livestock cooperative fertilizer plant to compare the composting period, temperature change, moisture content, and chemical properties between livestock manure compost using sawdust as a moisture regulator with those using spent oyster mushroom substrate. The composting period, moisture content, and fertilizer composition of compost containing spent oyster mushroom substrate did not differ from that of conventional compost mixed with sawdust after the first and second fermentation and post-maturation stages, it was suitable as a material for manufacturing livestock manure compost. The spent oyster mushroom substrate also lower the production cost of livestock manure compost by replacing the more expensive sawdust. The developed technology is expected to contribute towards the utilization of by-products of the oyster mushroom harvest while simultaneously producing high quality livestock manure compost.