• Journal of Korea Technology Innovation Society
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• v.17 no.2
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• pp.289-308
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• 2014

We analyze the risk factors identified for ex-ante evaluation regarding government R&D programs. In particular, we empirically examined to what extent each risk factor is perceived to be important by the stage of R&D, technology field, researcher's career and experience. The empirical results show that technology risk is perceive to be less important for basic research, while market risk more perceived to be important in the IT field. Political risk is perceived to be less important for the university faculty, while researchers with government R&D project experience gave more value to legal risk factor.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.153-159
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• 2018

In recent years, the development of weapons systems in the field of defense research and development has become increasingly large, complex, and long-term, and so have budgets and the time spans involved. In order to improve this, the Weapon Systems Requirement Verification Committee, which benchmarked the preliminary feasibility of the private sector, was established to verify the appropriateness of requirements, and the necessity and priority of the projects. This research proposes a methodology for analyzing and prioritizing proposed weapons systems for effective and strategic allocation of defense budget funding. First, the evaluation factors that can be used in the defense sector were assessed by analyzing the related fields. We set the weighting of items by using the analytical hierarchy process for technical risk assessment and technical profitability evaluation. After that, we applied the methodology to 32 weapons systems and analyzed the results. In conclusion, through this study, it was possible to analyze profitability dimensions overlooked in the existing methodology.

• Geomechanics and Engineering
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• v.12 no.4
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• pp.611-626
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• 2017

The research reported herein is concerned with the model testing of piles socketed in soft rock which was simulated by cement, plaster, sand, water and concrete hardening accelerator. Model tests on a single pile socketed in simulated soft rock under axial cyclic loading were conducted and the bearing capacity and accumulated deformation characteristics under different static, and cyclic loads were studied by using a device which combined oneself-designed test apparatus with a dynamic triaxial system. The accumulated deformation of the pile head, and the axial force, were measured by LVDT and strain gauges, respectively. Test results show that the static load ratio (SLR), cyclic load ratio (CLR), and the number of cycles affect the accumulated deformation, cyclic secant modulus of pile head, and ultimate bearing capacity. The accumulated deformation increases with increasing numbers of cycles, however, its rate of growth decreases and is asymptotic to zero. The cyclic secant modulus of pile head increases and then decreases with the growth in the number of cycles, and finally remains stable after 50 cycles. The ultimate bearing capacity of the pile is increased by about 30% because of the cyclic loading thereon, and the axial force is changed due to the applied cyclic shear stress. According to the test results, the development of accumulated settlement is analysed. Finally, an empirical formula for accumulated settlement, considering the effects of the number of cycles, the static load ratio, the cyclic load ratio and the uniaxial compressive strength, is proposed which can be used for feasibility studies or preliminary design of pile foundations on soft rock subjected to cyclic loading.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2116-2124
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• 2015

To understand the effects of physicochemical factors on nitrite transformation by microalgae, a lipid-rich Chlorella with high nitrite tolerance was cultured with 8 mmol/l sodium nitrite as sole nitrogen source under different conditions. The results showed that nitrite transformation was mainly dependent on the metabolic activities of algal cells rather than oxidation of nitrite by dissolved oxygen. Light intensity, temperature, pH, NaHCO₃ concentrations, and initial cell densities had significant effects on the rate of nitrite transformation. Single-factor experiments revealed that the optimum conditions for nitrite transformation were light intensity: 300 μmol/m²/s; temperature: 30℃ pH: 7-8; NaHCO₃ concentration: 2.0 g/l; and initial cell density: 0.15 g/l; and the highest nitrite transformation rate of 1.36 mmol/l/d was achieved. There was a positive correlation between nitrite transformation rate and the growth of Chlorella. The relationship between nitrite transformation rate (mg/l/d) and biomass productivity (g/l/d) could be described by the regression equation y = 61.3x (R² = 0.9665), meaning that 61.3 mg N element was assimilated by 1.0 g dry biomass on average, which indicated that the nitrite transformation is a process of consuming nitrite as nitrogen source by Chlorella. The results demonstrated that the Chlorella suspension was able to assimilate nitrite efficiently, which implied the feasibility of using flue gas for mass production of Chlorella without preliminary removal of NO_X.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.966-969
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• 2013

Vessel-based sighting surveys for cetaceans have been conducted in Korean waters since 2000. The supporting data estimate the abundance of finless porpoises along the west coast of Korea; however, they are insufficient because of the coverage and frequency of the surveys. A preliminary aerial survey was conducted in 2011, and the results were assessed with respect to a sighting survey operated by a research vessel in order to compare effectiveness and potentiality. A total of 110.00 nautical miles of effective efforts were made with three sightings under Beaufort scale 4 in the aerial survey, while the vessel-operated survey covered 403.38 nautical miles over 7 days without any sightings under Beaufort scale 4. The standard deviation of the altitude in this survey was 22.7 m, which was significantly higher than that of the referenced study of 4.3 m.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.2
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• pp.74-80
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• 2008

The feasibility study into the development of turbine spinners, which start up the turbo-pump, has been carried out and the design requirements and parameters ranges have been presented. Turbine spinners use the solid propellant as such composite propellant based AN compound with high energy plasticizers, coolants, and phase stabilizer which relieves a sensible volume change due to the phase transformation of AN near room temperature. Propellants which have a homing rate of $0.2{\sim}0.3\;mm/s$ and pressure exponent ranged from 0.3 to 0.6, showed stable burn-out in the standard motor tests. Both the magnitude of ignition energy and its thermal transfer mechanism have been proved to have a tangible effect on the ignition of the pyre starter, and the results of this study showed that a flame temperature of 1400K would be quite adequate to get a stable ignition for the AN composite propellant.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2280-2286
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• 2012

In this paper, we propose a novel nonlinear 3D image correlator using a fast computational integral imaging reconstruction (CIIR) method. In order to implement the fast CIIR method, the magnification process was eliminated. In the proposed correlator, elemental images of the reference and target objects are picked up by lenslet arrays. Using these elemental images, reference and target plane images are reconstructed on the output plane by means of the proposed fast CIIR method. Then, through nonlinear cross-correlations between the reconstructed reference and the target plane images, the pattern recognition can be performed from the correlation outputs. Nonlinear correlation operation can improve the recognition of 3D objects. To show the feasibility of the proposed method, some preliminary experiments are carried out and the results are presented by comparing the conventional method.

• Journal of The Korean Dental Society of Anesthesiology
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• v.2 no.2 s.3
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• pp.97-100
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• 2002

Background: Patient-controlled sedation (PCS) has been blown for a safe and effective sedative method on the same pharmacological concepts of patient-controlled analgesia. Many different kinds of infusion devices have been used but they often have too long nominal infusion rate and lockout time. $Perfuser^{\circledR}$ fm (B. Braun, Germany) is a new PCA device with 999.9 ml/hr nominal infusion rate and minimum 1 min lockout time. In this study, the feasibility of propofol PCS using $Perfuser^{\circledR}$ fm was examined in order to provide a safe satisfactory sedation for dental patients. Methods: Eleven healthy patients presenting for oral surgery were studied. Propofol PCS was performed using $Perfuser^{\circledR}$ fm, which was set to deliver a bolus dose of 5 mg with 999.9 ml/hr nominal infusion rate and 1 min lockout time. Propofol loading dose was randomly assigned to a bolus dose ${\times}$ 0, 2, and 3 (initial bolus). Patients were told to press the bolus button as often as they needed to relieve discomfort. Results: Total infused dose of propofol was mean 1.8 mg/kg/hr and D (Delivery)/A (Attempt) ratio was mean 72.8%. All patients was awake and there were no clinically significant intraoperative side effects during the sedation. Almost all patients were very satisfied with this type of PCS. Conclusion: Propofol PCS using $Perfuser^{\circledR}$ fm infusion pump provided good conscious sedation for dental procedures.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.1
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• pp.36-42
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• 2009

We have developed software for converting the volumetric voxel data obtained from X-ray computed tomography(CT) into computer-aided design(CAD) data. The developed software can used for non-destructive testing and evaluation, reverse engineering, and rapid prototyping, etc. The main algorithms employed in the software are image reconstruction, volume rendering, segmentation, and mesh data generation. The feasibility of the developed software is demonstrated with the CT data of human maxilla and mandible bones.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1693-1697
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• 2014

Background: The Bahcesehir Breast Cancer Screening Project is the first organized population based breast cancer mammographic screening project in Turkey. The objective of this prospective observational study was to demonstrate the feasibility of a screening program in a developing country and to determine the appropriate age (40 or 50 years old) to start with screening in Turkish women. Materials and Methods: Between January 2009 to December 2010, a total of 3,758 women aged 40-69 years were recruited in this prospective study. Screening was conducted biannually, and five rounds were planned. After clinical breast examination (CBE), two-view mammograms were obtained. True positivity, false positivity, positive predictive values (PPV) according to ACR, cancer detection rate, minimal cancer detection rate, axillary node positivity and recall rate were calculated. Breast ultrasound and biopsy were performed in suspicious cases. Results: Breast biopsy was performed in 55 patients, and 18 cancers were detected in the first round. The overall cancer detection rate was 4.8 per 1,000 women. Most of the screened women (54%) and detected cancers (56%) were in women aged 40-49. Ductal carcinoma in situ (DCIS) and stage I cancer and axillary node positivity rates were 22%, 61%, and 16.6%, respectively. The positive predictivity for biopsy was 32.7%, whereas the overall recall rate was 18.4 %. Conclusions: Preliminary results of the study suggest that population based organized screening are feasible and age of onset of mammographic screening should be 40 years in Turkey.