• Journal of Embryo Transfer
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• v.28 no.1
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• pp.7-12
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• 2013

Body condition score (BCS) is a useful management tool for distinguishing differences in nutritional needs of cows in the herd. Although it is not always possible to quantify the nutrient content of the feed supplied to the donor cow, the nutritional status can be determined by the BCS. The objective of this study was to evaluate in vivo embryo production, return to estrous of donor and pregnancy rate of recipients following BCS in Hanwoo superovulation. Sixty nine Hanwoo donor cows were flushed on day 7 of estrus cycle with same FSH and artificial insemination by the same technicians. Embryos were recovered on 7 days after the third insemination by flushing the uterus with Embryo Collection Medium. The results obtained were as follows: No differences were observed in the efficiency of superovulation rates regardless of BCS ($${\leq_-}2.0$$, 2.5 to 3.0, and $${\geq_-}3.5$$). The mean number of total embryos was each $5.20{\pm}0.86$, $11.56{\pm}1.04$, and $6.23{\pm}1.07$. The mean number of transferable embryo from $${\leq_-}2.0$$, 2.5 to 3.0, and $${\geq_-}3.5$$ of BCS was $2.60{\pm}0.87$, $7.94{\pm}0.89$, and $4.75{\pm}1.32$, respectively (p<0.05). Return to estrous regardless of donor BCS was no difference. The pregnancy rates of recipient were BCS $${\leq_-}2.0$$ 11.76%, 2.5 to 3.0 40.79%, and $${\geq_-}3.5$$ 11.11%, following transfer of fresh embryos produced in vivo, respectively. These results indicate that if the Hanwoo with BCS 2.5 to 3.3 are used for donor and recipient, the embryo production and the conception rate will be greater.

• Clinical and Experimental Reproductive Medicine
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• v.38 no.1
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• pp.24-30
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• 2011

Objective: The objectives of this study were to analyze efficacy of immature and mature mouse oocytes after vitrification and warming by applying various combinations of cryoprotectants (CPAs) and/or super-rapid cooling using slush nitrogen ($SN_2$). Methods: Four-week old ICR female mice were superovulated for GV- and MII-stage oocytes. Experimental groups were divided into two groups. Ethylene glycol (EG) only group: pre-equilibrated with 1.5 M EG for 2.5 minutes and then equilibrated with 5.5 M EG and 1.0 M sucrose for 20 seconds. EG+dimethylsulfoxide (DMSO) group: pre-equilibrated with 1.3 M EG+1.1 M DMSO for 2.5 minutes and equilibrated with 2.7 M EG+2.1 M DMSO+0.5 M sucrose for 20 seconds. The oocytes were loaded onto grids and plunged into $SN_2$or liquid nitrogen ($LN_2$). Stored oocytes were warmed by a five-step method, and then their survival, maturation, cleavage, and developmental rates were observed. Results: The EG only and EG+DMSO groups showed no significant difference in survival of immature oocytes vitrified after warming. However, maturation and cleavage rates after conventional insemination were greater in the EG only group than in the EG+DMSO group. In mature oocytes, survival, cleavage, and blastocyst formation rates after warming showed no significant difference when EG only or EG+DMSO was applied. Furthermore, cleavage and blastocyst formation rates of MII oocytes vitrified using $SN_2$ were increased in both the EG only and EG+DMSO groups. Conclusion: A combination of CPAs in oocyte cryopreservation could be formulated according to the oocyte stage. In addition, $SN_2$ may improve the efficiency of vitrification by reducing cryoinjury.

• Journal of Korean Philosophical Society
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• v.147
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• pp.261-281
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• 2018

This paper will cover recent discussions on the risks of human being due to the development of artificial intelligence(AI). We will consider AI research as artificial narrow intelligence(ANI), artificial general intelligence(AGI), and artificial super intelligence(ASI). First, we examine the risks of ANI, or weak AI systems. To maximize efficiency, humans will use autonomous AI extensively. At this time, we can predict the risks that can arise by transferring a great deal of authority to autonomous AI and AI's judging and acting without human intervention. Even a sophisticated system, human-made artificial intelligence systems are incomplete, and virus infections or bugs can cause errors. So I think there should be a limit to what I entrust to artificial intelligence. Typically, we do not believe that lethal autonomous weapons systems should be allowed. Strong AI researchers are optimistic about the emergence of artificial general intelligence(AGI) and artificial superintelligence(ASI). Superintelligence is an AI system that surpasses human ability in all respects, so it may act against human interests or harm human beings. So the problem of controlling superintelligence, i.e. control problem is being seriously considered. In this paper, we have outlined how to control superintelligence based on the proposed control schemes. If superintelligence emerges, it is judged that there is no way for humans to completely control superintelligence at this time. But the emergence of superintelligence may be a fictitious assumption. Even in this case, research on control problems is of practical value in setting the direction of future AI research.

• Korean Journal of Construction Engineering and Management
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• v.22 no.6
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• pp.15-23
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• 2021

As the construction production system is reorganized as part of the construction industry innovation plan, direct construction is expanding. According to this trend, this study analyzed the impact and problems of the expansion of direct construction through the position of the construction industry and a study of foreign cases. In addition, by diagnosing the impact of the measures to expand direct construction from various aspects, countermeasures were suggested to suitably apply the direct construction mandatory system. Also, for each alternative, effects and problems were evaluated through interviews with experts in policy/administrative and architecture fields. The alternatives for expanding and improving the efficiency of the direct construction mandatory system derived from this study are four items: granting the discretion of the client, differentiation by scale of construction, utilization of construction guarantee system, and introduction of flexible working group leader system. As a result of the expert interview, all of them were evaluated to have a positive impact directly and indirectly on the expansion of direct construction. This study contributes literature to the application of the direct construction mandatory system by examining the current status of direct construction, and suggests a direction for expanding direct construction through deduction of alternatives for applying the direct construction mandatory system and expert evaluation.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.373-383
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• 2021

Our society is aging rapidly. In this super-aged society, the increase in healthcare costs are considered a national problem that undermines the sustainability of social security. Various services for healthcare for the elderly have been promoted to address this. However, most of them have focused on healthcare after the outbreak of chronic diseases and lack preventive healthcare. Most of the preventive healthcare projects are only pilots. In this paper, the current status of health care services for senior citizens at home and abroad was analyzed and based on this, the limitations and improvements were analyzed to propose the establishment of IoT-based Total Silver Care Center. IoT-based Total Silver Care Center may be conveniently monitored the health status of the elderly through various sensors, medical devices, and smart bands. And based on this, it can improve the quality of nursing services through time-saving and work efficiency of nursing providers. In addition, health care interventions may be provided in a timely manner if there is a change in the health status of users. And real-time imaging systems can help overcome mental difficulties.

• Journal of Space Technology and Applications
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• v.2 no.2
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• pp.146-168
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• 2022

Witnessing current military conflicts in South China Sea and Eastern Europe, most defense analysts evaluate one of the most serious security threat toward the US is coming from the superpower competitions with Russia and China. The main means for such super power hegemonic competitions is military power and space power is a key enabler to maximize the efficiency and effectiveness of military employment. Reflecting above circumstances, the space hegemonic competition between the Unites States and China is spreading into all aspects of national powers. Under such an environment, R.O.K needs to significantly develop national space power to preserve life and assets of people in space. On the other hand, the R.O.K has a lot of limitations in launching space assets into orbits by land-based space rockets due to its geographic locations. The limitation of rocket launching direction, the failure to secure a significant area enough to secure safety and the limitation to secure open area enough to build associated facilities are among them. On this paper, I will suggest the need to build the 2nd space rocket launching site after analyzing a lot of short-falls the current 'Naro' space center face, compared to those of advanced space powers around the world.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.2D
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• pp.245-253
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• 2009

Road facility is the most fundamental infrastructure for traffic and various information for smooth traffic is included in road surfaces. Various information included in road surfaces should be often removed and reinstalled by partial damage and aging. In addition, the existing road surface information should be removed in order to mark new information as traffic information changes. The existing road surface removal method suing grinders and torches had problems such as dangerous working equipment and workers' direct exposure to cars. In addition, although water-jet system using super high-pressure water was used to remove road surface in order of improvement of traditional method, there are another problems such as limitations according to water-tanks and water frost on the road surfaces after work. Therefore, this study analyzes and suggests systems to develop prototype after analyzing dry ice blaster in order to improve the current road surface removal methods. In addition, the study analyzes the possibility of introduction of dry ice blaster through a test for proposing an automatized equipment for new road surface mark removal considering environment and work efficiency, and compare traditional method with introduced dry ice blaster for operating cost.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.433-439
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• 2023

In this study, the bonding performance of repair materials was evaluated on concrete repair surface to develop concrete repair materials based on UHPC (Ultra High Performance Concrete) which has high mechanical and durability performance. The ten test variables were applied considering the roughness and wet condition of the concrete surface subject to repair, the addition of polymer, and the use PP and PVA fibers in repair materials. The addition of the polymer caused a significant decrease in strength, which was thought to be due to the effect of the additional super plasticizer used to adjust workability. Also, flow was reduced by up to 13.8 % with the use of plastic-based fibers. As a result of evaluating the bond strength of the repair material considering the condition of the surface subject to repair, it was thought that in the case of using UHPC-based repair material, high bonding performance could be secured without any additional surface treatment as long as the surface of the base material was sound. In addition, UHPC-based repair materials showed high bonding performance even when the attachment surface was wet. In the future, research will be conducted on shot-crete application and gradient pouring for the development of UHPC-based repair materials, and continuous improvement in the repair material mixing property will be carried out to ensure economic efficiency and performance as a concrete structural repair material.

• Journal of the Korean Vacuum Society
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• v.20 no.3
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• pp.233-241
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• 2011

Currently, solar module is using the two methods such as a glass-filled method or a super-straight method. The common point of these methods is to use glass structure on the front of solar module. However, the reflectance of the solar module is high depending on the height of the incident sunlight due to the flat surface of the module front glass. Purposed to solve these problems, AG (anti-glare) structures were formed on the glass surface. Next is fabrication methods of AG structure. First, uneven structure made by micro blaster equipment was dipped in Hydro-fluidic acid (HF) acid. HF acid process was carried out to remove particles and to make high transmittance. The reflectance and transmittance of the anti-glare glass was compared to those of the bare glass. The reflectance of anti-glare glass decreased approximately 1% compared with bare glass. The transmittance of anti-glare glass was similar to bare glass. According to the sample angle, the difference of the reflectance between bare glass and the anti-glare glass was about 19%. Isc and efficiency value of anti-glare glass on bare solar cell appeared about 3.01 mA and 0.228% difference compared with bare glass. Anti-glare glass on textured solar cell appeared about 9.46 mA and 0.741% difference compared with bare glass. As a result, the role of anti-glare in the substrate is to reduces the loss of sunlight reflected from the surface. In this study, therefore, AG structure on the solar cell was used to improve the efficiency of solar cell.

• Journal of Climate Change Research
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• v.2 no.4
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• pp.283-295
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• 2011

Many actions against climate change have been taken to reduce greenhouse gases (GHGs) emissions at home and abroad. As of 2007, the GHGs emitted from buildings accounted for about 23 % of Korea's total GHGs emission, which is the second largest GHG reduction potential following industry. In this study, we introduced Carbon Zero Building (CZB), which was constructed by the National Institute of Environmental Research to cut down GHGs from buildings in Korea, and evaluated the main applied technologies, the amount of energy load and reduced energy, and economic values for CZB to provide data that could be a basis in the future construction of this kind of carbon-neutral buildings. A total of 66 technologies were applied for this building in order to achieve carbon zero emissions. Applied technologies include 30 energy consumption reduction technologies, 18 energy efficiency technologies, and 5 eco-friendly technologies. Out of total annual energy load ($123.8kWh/m^2$), about 40% of energy load ($49kWh/m^2$) was reduced by using passive technologies such as super insulation and use of high efficiency equipments and the other 60% ($74.8kWh/m^2$) was reduced by using active technologies such as solar voltaic, solar thermal, and geothermal energy. The construction cost of CZB was 1.4 times higher than ordinary buildings. However, if active technologies are excluded, the construction cost is similar to that of ordinary buildings. It was estimated that we could save annually about 102 million won directly from energy saving and about 2.2 million won indirectly from additional saving by the reduction in GHGs and atmospheric pollutants. In terms of carbon, we could reduce 100 ton of $CO_2$ emissions per year. In our Life Cycle Cost (LCC) analysis, the Break Even Point (BEP) for the additional construction cost was estimated to be around 20.6 years.