• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.145-148
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• 2001

Bi-2223/Ag HTS tapes fabricated by PIT process are used to make the power transmission cable, motor, fault current limiter, transformer etc. But some problems are still remained as like bubbling, sausaging to got the high Jc. In this study. we carried out the experiment to prevent bubbling in the HTS tape. The bubbling mainly occurred when HTS tape was heat-treating. Therefore, additional vacuum annealing at 400 ~ $600^{\circ}C$and slowly ramp-up sintering method were used to decrease the bubbling. slowly ramp-up sintering was more effective to decrease the bubbling than the vacuum annealing, but Jc was also decreased after heat treatment. Optimum ramp-up sintering schedule was searched to get the high critical current and prevent bubbling at same time.

• Journal of the Korean Ceramic Society
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• v.33 no.10
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• pp.1079-1088
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• 1996

Discontinuous ${\gamma}$-LiAlO2 fibers for fiber-reinforcing MCFC matrixes have been produced by the sol-gel process using the centrifugal spinning apparatus of the Rotary type. Gel fibers could be obtained through spinning of stable LiAlO2 complex polymetric sols under the optimum spinning conditions (hollow-disc rotating velocity 9000 rpm sol feeding rate of 4ml/min flowing N2 temperature of 4$0^{\circ}C$ and flowing N2 pressure of 4 bar). It was found that defect free and densified ${\gamma}$-LiAlO2 fibers with the relative density of 98% and the mean diameter of 4.7${\mu}{\textrm}{m}$ were prepared when the spinned fibers were heat-treated to 100$0^{\circ}C$ on the specified heating schedule. in particular the mean diameter and length of fibers could be controlled by the pressure of flowing N2 and the chopping-sieving method respectively.

• Nuclear Engineering and Technology
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• v.48 no.2
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• pp.495-504
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• 2016

International standards recommend typical phases to be included within any national program for the development of a geological repository dedicated to disposal of the high level radioactive wastes generated in countries using nuclear power. However, these are not universally applicable and the content of each of these phases may need to be adapted for each national situation and regulatory and institutional framework. Several national geological repository programs have faced failures in schedules and have revised their programs to consider an adapted phased management approach. The authors have observed that in the case of those countries in the early phases of a geological repository program where boundary conditions have not been fully defined, international recommendations for handling delays/failures in the national program might not immediately help. This paper considers a case study of the influences of the national context risks on the current planning schedule of the Romanian national geological repository. It proposes an optimum solution for an integrated response to any significant adverse impact arising from these risks, enabling sustainable program planning.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.505-508
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• 2006

Recently, concern for tidal power is being increased by newly recycled energy. It is important to decide on the maximum power estimate operation and it's stop by applying the difference of water level between tide level and artificial reservoir for the administration of tidal development. For maximum output of power through turbine generator, administrative variables and process on efficiency of hydraulic turbine and inflow discharge of reservoir is quite complicated because it is run through the connection of discharge-gate and turbine On the development of this model, the administrative process is decided, Operation block is presented for it's maximum power estimate.

• Structural Monitoring and Maintenance
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• v.2 no.2
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• pp.133-143
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• 2015

Civil engineering infrastructure is aging and requires cost-effective maintenance strategies to enable infrastructure systems operate reliably and sustainably. This paper presents an approach for determining risk-cost balanced repair strategy of corrosion damaged reinforced concrete structures with consideration of uncertainty in structural resistance deterioration. On the basis of analytical models of cover concrete cracking evolution and bond strength degradation due to reinforcement corrosion, the effect of reinforcement corrosion on residual load carrying capacity of corroded reinforced concrete structures is investigated. A stochastic deterioration model based on gamma process is adopted to evaluate the probability of failure of structural bearing capacity over the lifetime. Optimal repair planning and maintenance strategies during the service life are determined by balancing the cost for maintenance and the risk of structural failure. The method proposed in this study is then demonstrated by numerical investigations for a concrete structure subjected to reinforcement corrosion. The obtained results show that the proposed method can provide a risk cost optimised repair schedule during the service life of corroded concrete structures.

• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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• pp.20-27
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• 2015

The juice carrier is the first ship built in korea. Special refrigerator system and cargo hold insulation with stainless steel tank were equipped on cargo hold. We studied optimum design of cargo hold insulation for reducing of ship building schedule and cost including good quality with refrigerating efficiency. From this study, general and newly specified juice carrier, technical method of cargo hold insulation system, air flow with division air wall, K-value calculation have been investigated.

• Culinary science and hospitality research
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• v.12 no.1 s.28
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• pp.188-202
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• 2006

With large corporations entering into the foodservice market, competitions among those foodservice providers became intense, leading to differentiated quality services in terms of portioning out the meal, its portion and waiting time, not to mention food quality. The purpose of providing foodservice is to satisfy its customers, to secure optimum level of profits, and attain continuous quality improvement. To have such purpose attained, all other factors affecting the foodservice should be allowed to play a role. The intensity of the work performed by the employees should be maintained at a steady level and systematically controlled. 'Service First’ principles upholding that customer satisfaction comes from good service should be applied at all times; customer satisfaction comes from the satisfaction of the employees. Customer satisfaction through good service will contribute to an increase in revenue which we get by subtracting operating expenses from the total sales, as it will lead to concluding a long-term supply contract or renewing the existing contract. To keep the operating expenses to the minimum level, it is important to effectively perform the cost control. Since personnel expenses occupy a large portion of the operating expenses, it is imperative to effectively control the labor costs. For this reason, this study will present an effective program for disposition of men with a large organization being centered around, where the number of people served at the mess hall varies greatly depending on a day of the week and a mealtime of the day.

• Korean Journal of Construction Engineering and Management
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• v.17 no.3
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• pp.43-51
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• 2016

Recently, the cost of construction projects has escalated due to a significant increase in size and complexity. Many construction projects have failed to meet their originally intended project deadline due to various factors such as weather, labor supply, equipment, procurement, accidents, etc. Consequently, emergency construction work scenario has to be implemented in order to shorten the duration and satisfy the original estimated schedule. However, many critical decisions in emergency scenario rely solely on the experience of a construction manager. Thus, this paper proposes TCTO optimization model to decide the most effective alternative out of various working scenarios which are generated by the combination of work group and work time. The developed TCTO model provides the optimum schedule that satisfies the practical constraints. Future research could involve the integration of resource leveling with the proposed model. This would make the model more versatile.

• Journal of the Korean Wood Science and Technology
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• v.42 no.1
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• pp.13-19
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• 2014

Three heat-treatment schedules were applied to $90{\times}90mm$ dimension square lumber of Pinus koraiensis, one of major domestic species, and their colors and physical properties were investigated for obtaining an optimum schedule. Each square lumber was heat-treated three times. The temperatures of $170^{\circ}C$ and $190^{\circ}C$, and the time of 9 hours and 13 hours were used for the first heat-treatment. The schedule of $190^{\circ}C$ and 7 hours were used for the next two heat-treatments. The averages of brightness $L^*$ decreased linearly as the heat-treatment repeated and its standard deviations also decreased slightly. While the averages of color difference ${\Delta}E^*$ increased linearly as the heat-treatment repeated and its standard deviations also increased slightly. The average compressive strength of the heat-treated specimen was higher than that of the control by 9%, which deviates from previous reports. ASE and WPG of the heat-treated specimens were measured to confirm that heat-treatment improved dimensional stability significantly.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.632-636
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• 2005

This study was conducted to investigate the effects of removal of all ovarian follicles through repeated transvaginal follicle aspiration (TVFA) on the subsequent follicular populations in buffaloes. This information is crucial for determining the optimum time interval between successive aspirations for recovering oocytes from live buffaloes through Transvaginal Oocyte Retrieval (TVOR). The oestrus of cycling buffaloes (n=5) were synchronized by a single PGF injection schedule. All the ovarian follicles were removed once every 7 days for 6 weeks through TVFA, starting from Day 7 of the oestrous cycle (Day 0 = day of oestrus). The number and size of individual ovarian follicles was recorded at Day 3 and Day 5 (Day 0 = day of TVFA) through transrectal ultrasonography. The follicles were classified on the basis of their diameter as small (3-5 mm), medium (6-9 mm) and large ($\geq$10 mm). There was no difference in the number of small and medium follicles, and the number of total follicles between Day 3 and Day 5. However, the number of large follicles was significantly higher (p<0.05) at Day 5 than that at Day 3. There was a significant (p<0.05) decrease in the proportion of small follicles and an increase (p<0.05) in the proportion of large follicles from Day 3 to Day 5, with no change in the proportion of medium follicles. The number of total follicles at Day 3 or Day 5 did not differ during the 6 TVFA sessions. It can be concluded that an interval of 3 days is more suitable than that of 5 days between successive aspirations for recovering oocytes through TVOR in a twice weekly schedule and that repeated removal of follicles through TVFA does not adversely affect the number of total follicles 3 or 5 days after TVFA.