• Journal of the Korea Institute of Building Construction
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• v.23 no.4
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• pp.465-476
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• 2023

This study introduces the development of a precast concrete double-wall, applicable to basement construction in apartment buildings. Unlike traditional precast concrete double walls, the developed double-wall doesn't require specialized manufacturing equipment such as a lathe. The constructability of these advanced technologies was validated through a full-scale mock-up test using the precast concrete double wall. The test specimens were constructed to represent a structural wall with a thickness of 250mm. It was observed that the quality of the in-situ concrete, filled between two single panels of 110mm thickness each, was excellent. The construction efficiency of the developed double-wall system for basement construction in an apartment building was also examined. Expert interviews about installation times of precast concrete elements were conducted to evaluate the speed of the basement floor's installation. The results showed that installation of precast concrete elements, including the proposed double walls, could be completed within 20 to 29 days for a basement in an apartment building. This indicates a three-fold increase in construction efficiency compared to traditional methods relying on in-situ casting.

• Journal of Christian Education in Korea
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• v.72
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• pp.49-70
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• 2022

The purpose of this study is to suggest a response and solution through Christian educational care to the crisis and change of the era of low birth rate faced by Korean society and the Korean church. This study proposes to find an alternative to the biblical aspect of pregnancy, childbirth, and parenthood as God's blessing for the demographic cliff and low birth rate problem that have become a reality in Korean society and churches. Being a parent in an age of low birth rate is very difficult, but on the other hand, it gives happiness and joy. Being a parent is a blessing from God, and is the most important and valuable thing in life. However, modern society emphasizes the right and necessity to choose one's own parenthood status. In the nuclear family, the decrease in the number of children, and the development of child research, parents feel more responsibility and economic burden for raising children than ever before. Therefore, it is a reality that the number of people who delay becoming parents or voluntarily do not have children is gradually increasing. To improve the perception of becoming a parent due to a decrease in responsibility for raising children, it is necessary to shed light on marriage, pregnancy, childbirth, and childrearing from a Christian educational point of view. In addition, it is necessary to understand the recognition of being a parent and the characteristics of childbirth and rearing, and to analyze past and present value changes. This study will also discuss the causes of low birthrate and try to provide Christian educational care for childcare including solving the low birthrate problem.

• The Journal of Bigdata
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• v.8 no.1
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• pp.23-34
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• 2023

Nowadays, the Designated Driver Services employ dynamic pricing, which adapts in real-time based on nearby driver availability, service user volume, and current weather conditions during the user's request. The uncertain volatility is the main cause of price increases, leading to customer attrition and service refusal from driver. To make a good Designated Driver Services, development of a demand forecasting model is required. In this study, we propose developing a demand forecasting model using data from the Designated Driver Service by considering normal and peak periods, such as rush hour and rush day, as prior knowledge to enhance the model performance. We propose a new methodology called Time-Series with Conditional Probability(TSCP), which combines conditional probability and time-series models to enhance performance. Extensive experiments have been conducted with real Designated Driver Service data, and the result demonstrated that our method outperforms the existing time-series models such as SARIMA, Prophet. Therefore, our study can be considered for decision-making to facilitate proactive response in Designated Driver Services.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.553-560
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• 2023

The study is about domestic industries following the migration of hubs (innovation, manufacturing) to other countries and the hub-oriented US industries (batteries, semiconductors, electric vehicles). Additionally, the ongoing trade tensions between the United States and China may have also played a role in companies moving their operations to the United States. The result of such a move could potentially include job creation in the United States, as well as increased investment in the U.S. manufacturing sector. However, it is also possible that there could be negative consequences, such as higher prices for consumers or disruptions to supply chains during the relocation process. However, such IRA, Chips Act scenario would likely also have negative consequences (Inflation in the home country) for the countries whose industries moved to the US, as they would lose jobs, investment, and possibly face economic difficulties as a result. As the result of the empirical analysis of the export scale of Korea and the United States, changes in the movement of global supply hubs are related to factors such as geopolitical price increases and consumption declines. In order to respond to these changes, this paper emphasizes the need to prevent the result of de-advantage by moving the production area of the scale.

• Resources Recycling
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• v.32 no.3
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• pp.3-8
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• 2023

This study discussed production, demand, and future prospects of rubidium, which is an alkali group metal that is highly reactive to various media and requires carefulness in handling, but no significant environmental hazard of rubidium has been reported yet. Rubidium is used in various fields such as optoelectronic equipment, biomedical, and chemical industries. Because of difficulty in production as well as limited demand, the transaction price of rubidium is relatively high, but its detail information such as market status and potential growth is uncertain. However, if the mass production of versatile ultra-high-performance equipment such as quantum computers and the necessity of rubidium use in the equipment are confirmed, there is a possibility that the rubidium market will expand in the future. Rubidium is often found together with lithium, beryllium, and cesium, and may be present in granite containing minerals such as lepidolite and pollucite, as well as in seawater and industrial waste. Several technologies such as acid leaching, roasting, solvent extraction, and adsorption are used to recover rubidium. The maximum recovery efficiency of the rubidium from the sources and the processing above is generally high, but, in many practices, rubidium is not the main recovery target, and therefore the actual recovery effects should depend on presence of other valuable components or impurities, together with recovery costs, energy consumption, environmental issues, etc. In conclusion, although the current production and consumption of rubidium are limited, with consideration of the possible market fluctuations according to the emergence of large-scale demand sources, etc., further investigations by related institutions should be necessary.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.547-558
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• 2008

With the advent of super cargo ship due to the explosive increase in the amount of cargo shipped via seas, some mega ports are under construction in South Korea, to accommodate the super cargo ship, and some of them already enter their final phase. To sustain the harbor tranquility, mega ports usually comprise huge vertical type breakwaters which are intrinsically vulnerable to the attack of long waves. In this rationale, we present the chamber type breakwater with a circular curtain wall - Eco-breaker 2, to alleviate the reflection of long waves and numerically investigate the hydraulic characteristics of Eco-breaker 2. As a wave driver, we use the Navier-Stokes eq., the most robust wave driver, using SPH (Smoothed Particle Hydrodynamics) and LES (Large Eddy Simulation). For the verification of numerical results, we also carried out hydraulic model test. It is shown that Eco-breaker 2 can effectively alleviate the reflection of long waves with its inherited large organized eddies encompassing the water chamber and some region off the curtain wall of varying size. It is also shown that the scope and strength of large organized eddies strongly depends on the incident wave period, and the reflection coefficient can be lowered to 0.18 by tuning the size of water chamber such that resident time at the chamber is just short of the half period of incident waves. Based on these results, we present the specification of Eco-breaker 2 to boost its use on the development of water environment friendly harbor worldwide.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6D
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• pp.839-847
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• 2008

No proper system exists for private investment projects, and efficient project management is not being achieved due to entanglements of management. Recognizing these circumstances, this paper has diagnosed the hard facts that project management organizations and systems are facing, and presented solutions to the factors that are obstructing the establishment of efficient project management system. This paper carried out focus group interviews on the experts who had participated in the Incheon International Airport Railway construction project, using the methodology of an exploratory case study. The results were systematically analyzed according to organizational behavior and causes corresponding to each of the problems were deduced. Private investment projects were divided into task environments and project organizations based on social science methodology and analyzed, and a final improvement plan for each participating organization was presented. An improvement plan was presented, and it was compared with the case study of Incheon bridge construction project, which is recognized as a model of successful project management, and its appropriateness evaluated.

• 한국노년학
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• v.30 no.4
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• pp.1213-1223
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• 2010

The purpose of this study is to explore and describe the health and welfare needs experienced by old parents living with disabled adult children, and to help generate research interest and public policy attention on this critical issue. For the purpose of this study, the survey was conducted with older parents who are living with dependent adult children with physical or mental disability. Among collected data for this study, data for 105 older parents were analyzed. The results showed that older parents have suffered with care responsibilities for their disabled adult children as well as special needs resulted from their old age. And older parents have little or even nothing prepared for later life because of lifetime economic, physical and social difficulties related to their disabled children. Also these difficulties had a significant impact on their idea of health and welfare needs in later life. It showed that older parents had mainly concerned and wanted to have the direct cash benefits and medical provisions but hardly recognised the importance of other services such as leisure activities. Preliminary suggestions of this study therefore may be helpful to improve the public policy approach in order to better serve older parents with disabled adult children in the coming aging society.

• Issues in Feminism
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• v.10 no.1
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• pp.123-158
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• 2010

For the last several months, abortion debates have sparkled in Korea. The government has escalated the need of active punishment of illegal abortions to solve low fertility problems, while some obstetricians and gynecologist have proclaimed stoppage of illegal abortions suing colleague doctors who has conducted illegal abortions. Women's rights groups and researchers have also responded to the abortion debate claiming that women's decisions over their pregnancy are important in making of abortion policies. To contribute to Korean abortion debates, his paper aims to analyze European experiences of abortion polices in relation to the consequences on women's health. For the analysis of European abortion experiences, three countries - Ireland, U.K, and Netherland -are chosen. These three countries are selected since their legal and social acceptance of abortion and the level of safe abortion system are different. Each country is reviewed by national abortion policy, legal regulation, medical system and the role of civil society. The analysis shows several implications for abortion debates occurring in Korea. Various systematic policy mechanisms - abortion on women' request, abortions without complicated doctor's referrals, transparent and anonymous counseling and information provision regarding abortion, training and education for medical professionals to guarantee high quality abortion, abortions funded publicly for women to improve their access to abortions, steady monitoring and auditing abortion procedures and outcomes for safe abortion and so on - are required in Korean society. Two track procedures - safe abortion on women's request and prevention of unwanted pregnancy - are needed for reproduction of healthy women and society.

• Korean Journal of Construction Engineering and Management
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• v.24 no.6
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• pp.63-65
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• 2023

BIM and AR technologies have been assessed as a means of enhancing productivity within the construction industry, through the provision of effortless access to critical data on site, achieved via the projection of 3D models and associated information onto actual structures. However, most of the previous researches for applying AR technology in construction quality management has been performed for construction projects in general, resulting in only overall on-site management solutions. Also, a few previous researches for the application of AR in the quality management of specific elements like reinforcements focused only on simple projection, so conducting specific quality inspection was impossible. Hence, this study aimed to develop a practically applicable BIM-based AR quality management system targeted for reinforcements. For the development of this system, the reinforcement inspection items on the quality checklist used at railway construction sites were analyzed, and four types of AR functions that can effectively address these items were developed and installed. The validation result of the system for the actual railway bridge showed a degradation of projection stability. This problem was solved through model simplification and enhancement of the AR device's hardware performance, and then the normal operation of the system was validated. Subsequently, the final developed reinforcement quality inspection system was evaluated for practical applicability by on-site quality experts, and the efficiency of inspection would significantly increase when using the AR system compared to the current inspection method for reinforcements.