• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.3
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• pp.161-169
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• 2017

The present study investigated the effect of the rib arrangement and a guide vane for enhancing internal cooling of the blade. Two types of rib arrangements were used in the first and second passage in parallel. Aspect ratio of the channel was 5 and a fixed Reynolds number based on hydraulic diameter was 10,000. The attack angle of rib was $60^{\circ}$, rib pitch-to-height ratio (p/e) was 10, and the rib height-to-hydraulic-diameter ratio ($e/D_h$) was 0.075. The effect of an interaction between Dean vortices and the secondary vortices from the first passage was observed. Overall, the attack angle of rib in the first passage was dominant factor to heat transfer and flow patterns in turning region. Also, the channel with a guide vane showed enhanced heat transfer at the tip surface with reducing flow separation and recirculation.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.05a
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• pp.210-214
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• 2006

Along with the development of industrious society, the shape of city and the way of life have changed in accordance. The development of the city deepened gravitation of the city population, leading to the lack of housing and land, and apartment complexes became an alternative way of securing a number of families into a small space of land. Apartment can have a lot of families reside In a small space of land, and it can also be satisfactory to individual's privacy and anti-crime measures. On the other hand, there are negative problems with it. Among them, contacts with neighboring people showed that they only greeted each other when they met in the walkway. As shown in this, one of the reasons that there is a lack of friend ship activities is because there is short of space for common use. And in comparison to those of stairway walkway, apartments with one-passage walk way showed a higher level of contacts with neighbors. It is assumed that apartments with one-passage walk way have more chances to meet neighbors than do those of stairway walkway. This study analyzed the phases appearing in neighbor relations through investigation of the literature, and presented a coping measure. One solution is to prepare flower beds from the outside of walkway by enlarging the width of the walkway in apartments with one-passage walk way, and providing benches in front of flower beds so that residents can take a rest there. The more often residential people take a rest there, the more frequently they can meet each other. Accordingly this can solve problems of contacts with neighbors and the dreary scene of walkway can become a wider view in a nature friendly environment, bringing them to an active acquaintance activities.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.10
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• pp.969-978
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• 2008

In a linear cascade experimental apparatus, when it adopts only few blades as well as satisfies the periodic condition between blades, it gives several advantages in experiment. In this study, wall design on a cascade experimental apparatus is conducted to obtain the periodic condition on two blades installed within a passage of which the width is double pitch. The Mach number difference on the blade surface obtained with the periodic and wall condition is chosen as an objective function, and twelve design variables which are related to the wall shape are selected. A wall shape is designed using a gradient-based optimization method. Adjustment of range and weighting function are applied to calculate the objective function to avoid unrealistic evaluation of the objective function. By applying these methods, the computed results show same flow structures obtained with the periodic condition.

• Korean journal of food and cookery science
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• v.23 no.1 s.97
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• pp.140-149
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• 2007

This study investigated the thoughts of undergraduate students in Seoul about the birth rites and wedding ceremony and their foods. Among 524 students who were surveyed, 299 students answered that the meaning of the first birthday rites was for special memory, followed by the child's future and family's harmonies. 248 desired birth rites to remain unchanged and 150 desired extravagance and waste to be reduced. Regarding wedding ceremony, 328 answered that changes are necessary in wedding ceremony gifts. Next, process in wedding ceremony and bridegroom's gift box should be changed, Most of the students didn't know clearly the foods of the one hundredth birthday and the first birthday; nevertheless they considered the birth rites to be necessary. Regarding wedding ceremony, half of the students knew the process and half didn't. Two hundred students answered they knew ordinarily about the foods of wedding ceremony. There were no significant differences in hometown about foods of wedding ceremony. In parent's religions, there were no differences about gifts & foods offered by the bride. The Buddhist students knew well about the birth rites' foods and considered birth rites to be necessary. The correlation of parents' work and student's major and passage rites showed that professional parents knew well about birth rites' foods but religious believers didn't know well. Students majoring in natural science were not concerned with birth rites and thought that they were unnecessary and they didn't know about wedding ceremony process and foods. Knowledge about birth rites increased with increasing number of siblings. Large families were interested in birth rites and knew well about the wedding process, wedding ceremony foods and gift & foods offered by the bride.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.6
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• pp.385-392
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• 2022

Naval ship could face a variety of threats in isolated seas. In particular, fires and flooding are defined as disasters that are very likely to cause irreparable damage to ships. These disasters have a very high risk of personal injury as well. Therefore, when a disaster occurs, it must be quickly suppressed, but if there are people in the disaster area, the protection of life must be given priority. In order to quickly evacuate the ship crew in case of a disaster, we would like to propose a plan to quickly explore the evacuation route even in urgent situations. Using commercial escape simulation software, we obtain the data for deep neural network learning with simulations according to aisle characteristics and the properties and number of evacuation person. Using the obtained data, the passage prediction model is trained with a deep learning, and the passage time is predicted through the learned model. Construct a numerical map of a naval ship and construct a distance matrix of the vessel using predicted passage time data. The distance matrix configured in one of the path search algorithms, the Dijkstra algorithm, is applied to explore the evacuation path of naval ship.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.655-659
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• 2004

Performance tests of the fuel pump for a turbopump unit have been successfully carried out in water environment. The tests are performed to evaluate the hydraulic and cavitation performances. The head and volute pressure distribution of the fuel pump followed the conventional similarity rule - unlike this, the secondary passage pressure distribution showed a small deviation from the conventional similarity rule. Also, critical cavitation number decreased as the rotational speed of the pump increased.

• Radiation Oncology Journal
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• v.17 no.2
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• pp.158-165
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• 1999

Purpose : To investigate the percentage of colonies wi1h16or more cells distribution of human skin fibroblast according to in vitro aging, and to evaluate the relationship between percentage of colonies with 10 or more cells and in vivo donor age in human skin fibroblast culture. Material and Method : C1, C2, C3a, and C3b human skin fibroblast samples from three breast cancer patients were used as subjects. The C1, C2, and C3a donor were 44, 54, and 55 years old, respectively. C3a and C3b cells were isolated from the same person. Single cell suspension of skin fibroblasts was prepared with primary explant technique. One hundred cells are plated into 100m1 tissue culture flask and cultured for two weeks. The colony size was defined as colonies with 16 or more cells. The cultured cell was stained with crystal violet, and number of cells in each colony was determined with stereo microscope at $\times$10 magnification. Passage number of C1, C2, C3a and C3b skin fibroblast were 12th, 17th, and 14th, respectively. Results : Percentage of colonies with 16 or more cells of skin fibroblast samples decreased with increasing in vitro passage number. In contrast, cumulative population doublings of skin fibroblast sample increased with increasing in vitro passage number. Percentage of colonies with 16 or more cells also decreased with increasing population doublings in human skin fibroblast culture. There was strong correlation with percentage of colonies with 16 or more cells and population doublings En C3a skin fibroblast sampie. At the same point of population doublings, the percentage of colonies with 16 or more cells of the young C1 donor was higher level than the old C3a donor. Conclusion : The population doublings increased with increasing in vitro passage number but percentage of colonies with 16 or more cells decreased. The results of this study imply that percentage of colonies with 16 or more cell is useful as a indicator of in vitro human skin fibroblast aging and may estimate the in vivo donor age.

• Journal of Power System Engineering
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• v.21 no.1
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• pp.70-79
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• 2017

The output power of turbine is greatly affected by the losses generated within the passage. In order to develop a better turbine or loss models, an experimental study was conducted using a linear cascade experimental apparatus. The total pressure loss and flow structures were measured at two cross-sectional planes located downstream of blade row. Measurement was conducted in a steady state for the several different locations of the blade row along the rotational direction. The blade row moved by 20 % of the pitch, and tip clearance was varied from 2% to 8%. Axial-type blades were used and its blade chord was 200mm. A square nozzle was applied and its size was $200mm{\times}200mm$. The experiment was conducted at a Reynolds number of $3{\times}10^5$ based on the chord. Nozzle flow angle sets to $65^{\circ}$ based on the axial direction and the solidity of blade row was 1.38. From the experimental results, the total pressure loss was greatly varied in the receding region than in the entering region. The flow properties within the blade passage were strongly changed according to the location of blade row.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.2
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• pp.62-72
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• 2004

In this paper. firstly, numerical results were compared with experimental results to verify accuracy of the results. It is found that the numerical results show good agreements with experimental result. Next, computations about flow within blades for design parameters such as radius of the pressure and suction side's curvature and pitch-chord ratio have been performed. It is found that the flow and performance characteristics mainly depend on shocks occurred at the leading edge of blades and the end of nozzle and separations occurred inside the flow passage. And shock of nozzle and separations depend upon area of flow passage and shocks of blade are affected by the number of blades occupied by a nozzle.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.13-17
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• 2006

Almost every day close passage or near miss events happens in south part of Istanbul Strait between the vessel runs in the local area and pass strait transit. The vessels run in the local area pass close bow or aft of transit vessel or come close and wait for transit vessel because of inexperienced or incompetent skipper or because of time limitation or failure in technical equipment or lack of technical equipment or old equipment. This close passages create profound dangers for the surroundings. By the this research has been aimed to point out mentioned dangers by the concrete as number. For this purpose has been utilized JMS Ship Handling Simulator which has been settled in ITU Maritime Faculty and Environmental Stress Model which has been built up and improved in Inoue Laboratory. Has been put in the senarios which been played during simulation implementations transferred to the numerical risk occured during passage of South Part of Istanbul Strait by the Environmental Stress Model . Thus so, the riskwhich Istanbul Strait face everyday has been expressed as numerical and concrete.